MDL
Samuel Roy Helwig
Does anyone in this group remember MDL (muddle)? I was told that
the original Adventure was written in it. It seems that it was an
interactive fiction game language. Is this true? Also, I was told that
the Infocom text-based games were written in a language based on a
subset of MDL. Finally, if anyone has the original Adventure source (in
MDL) or anything else in MDL, I'd like to look at it.
thanx,
Sam
Barry Margolin
> Does anyone in this group remember MDL (muddle)? I was told that
>the original Adventure was written in it.
No, Adventure was originally written in Fortran. The original Zork was
written in MDL.
> It seems that it was an
>interactive fiction game language. Is this true?
Not really. MDL was a variant of Lisp, used by a small group at the MIT
Laboratory for Computer Science (the Dynamic Modeling group) in the 70's.
Many of its distinguishing features (better abstract data type support, in
particular) eventually found their way into Common Lisp. Lisp-like
languages are pretty good for writing natural language parsers and managing
highly-connected object structures, and this is presumably why the Zork
authors used it (Zork was the first adventure game that permitted free-form
sentences as commands, rather than requiring rigid adherence to a simple
syntax).
--
Barry Margolin
System Manager, Thinking Machines Corp.
bar...@think.com {uunet,harvard}!think!barmar
Charles Lasner
Adventure was written in PDP-10 Fortran. Later it was bastardized down to
run on the PDP-11 Fortran. Later still, the -11 version was made to run
in 32K on the PDP-8. (I believe that certain features of the original
source would have been better to migrate than the -11 version when bringing
it to the -8 because both the -10 and -8 version support 36 bit variables.)
The -8 version is now available for the DECmate II, III, III+.
The -11 (and indirectly the -8) version port was done by Bob Subnik, originally
of DEC.
Various MIT students wrote MDL and the game ZORK in it. It was their "answer"
to Adventure, and is somewhat more complex and difficult, and has some
sections that are clearly "borrowed" from Adventure. For example, Adventure
has a section where the room names are unique, but so similar, you can easily
get lost. You are in a twisty little maze of passages, all different is
*not* quite the same as you are in a little twisty maze of passages, all
different, etc. Zork has a similar region requiring the same fortitude to
get through. However, it also has another area where they have a similar
name, but are literally identical to trick you. Also, there is another
section described nonuniquely as a nondescript portion of a coal mine. Still
another region is laid out mostly as a mirror image of another section. Some
rooms have random exits, and the exit conditions change as a function of the
state of the game.
Eventually, Infocon hired some of the MIT students and also Bob Subnik. There
is some confusion regarding the exact chronology of who had/took various
files from MIT but in any case, there was at one point a Fortran-based ZORK
that was known to be a hacked-up Adventure game with data taken from the
MDL version, but the commands were simplified because Adventure's command
parser is feeble by comparison to ZORK, even from the beginning. The game
scoring of ZORK is such that there are some semi-critical paths in the sense
that you have to get through regions of the game in a reasonable number of
moves, or you lose sources of light. Some of the counting of said moves
involve using some of the more compound usages of the commands such as
TAKE ALL VALUABLES. The stupid Adventure parser needs for you to do commands
like that in several moves. Thus, when you can't type THROW AXE AT DWARF
and instead have to type THROW AXE, and be asked at what? and answer AT DWARF
you take more turns. As such, that version had to relax certain mechanisms
of the game to make it playable in this distorted form. Eventually, a version
that was much smarter appeared in DECUS replacing the hacked-up one that had
a better parser. This version has even been ported to MS-DOS. As far as
I understand, it is fairly faithful to a popular "vintage" of the -10-based
MDL version, but not the latest version available there. Apparently more
features were added, and you have to do more work to be reincarnated, although
this allows a "ghost" mode, and there are more points to earn to win a
maximum score. Does anyone know if the MS-DOS version supports a "Real"
version of the endgame?
There has also been published a piece of artwork that is a map to the
original version. It is "creative" enough to avoid certain minor details,
such as one I noticed in the -20 version vs that hacked-up version that I
played on VMS version 1.0: There is a direction out of one of the
twisty maze rooms to connect to another room. The specific direction is
something like SE, while in the hacked-up version which MIT never authorized,
it is SW. The map can be used regardless due to clever drawing. I believe
it was done by Steve Roy of DEC, and was published by the DEC Professional
people (possibly called RSTS Professional back then?).
Infocon changed the game in ways that are offensive to any seasoned player:
They continued to enhance the parser in likely not-very-important ways, which
isn't problematic, but they *broke* the game up into 3 parts merely to
satisfy the requirement that each part could fit into a 64K CP/M system
without swapping. This "proscribes" parts of the game, and enforces where
you start at part 2 and part 3, etc. Moreover, they changed the game
somewhat, adding and deleting features that where specific to the original
and replacing them with features that in some people's opinions aren't
consistent with the prose-style of the original Adventure and ZORK. (Both
are similar in style, not particulars.)
I understand that they continued development on a PDP-10 for these games,
and that the development language became known as ZIL, later DDL.
Eventually, they brought out MS-DOS versions of these games, but they ran
from paranoidly copy-protected disks with disk copy counts (you can't copy
a copy, and an original can only be copied twice), not from a true
MS-DOS system disk. Again, the 64K restriction was applied, so the
PC versions are "compatible" with the CP/M ones.
Various people have broken into these disks, and floating around internet
are MS-DOS files that run directly under MS-DOS of the three files in the
"Zork Trilogy" as they call it, including solve files for all three. Looking
at the solve files, I see that there is only faint resemblance to the
faithful ZORK version which is also floating around the net, possibly in
source form. It would derive from the version in DECUS for the VAX and -11,
which points out that Bob Subnik is the latest author, and that it's the last
non-commercial version that will be available. As far as I know, the
MDL version with the extended features is the only complete version with
the extended scoring and full end-game capabilities. (I think the DECUS
and previous MDL versions can be identified by the max score of 585 and
the newest features are the Bank of Zork with the Gnome of Zurich, and
the large tree with the songbird, while the last MDL-only version scores
something like 616 points and has the ghost mode and complicated
reincarnation plus additional features. An expert player who solved the
DECUS submission to the full 585 points wasn't able to get any higher with
the last ZORK version, although he had little time to attempt to find more
features. In his opinion, all added was upward compatible, because he
found nothing different as he acquired his full score, yet not enough
to fully "win" the game.)
I assume that some of the people with KS20 systems at home can run this
more advanced MDL version; perhaps they can fill us in on the additional
features and scoring points, etc.
Floating around the net is also a C-based version of Adventure that the
authors were extremely careful to be faithful to the original. They point
out a few bugs in the original, but in all other ways it's the same. There
are even compatibility switches to handle certain quirks to be as compatible
as anyone would want, etc.
Had the Infocon version of Zork been as faithful, more people would be
complaining less about it. As it stands, it is perceived as a sleazy way
to make money off of a college hack. Since the files were taken, MIT
did obtain a copyright on the program to prevent further misuse.
cjl
Jeremy Fitzhardinge
I suspect that MDL is very old. There is a newer system, ADL (Adventure
Definition Language), which I think is based on MDL. ADL is a lispy
language that's quite easy to do things in. It comes with a few
sample adventures, and its not particualarly difficult to work with.
I cowrote a lift with 4 floors which the player could use, as well as the
computer controlled security guard who wandered about. There were numerous
details that got the button press/lift arrival right. It only took a few
hours one morning between about midnight and 7.
J
--
jer...@sw.oz.au ph:+61 2 698 2322-x122 fax:+61 2 699 9174
The pumpkin. The sheep. My brother's wife.
Magnus Olsson
>Various MIT students wrote MDL and the game ZORK in it. It was their "answer"
>to Adventure, and is somewhat more complex and difficult, and has some
>sections that are clearly "borrowed" from Adventure.
IMHO, these "borrowings" are more in the nature of a homage to Advent
than plagiarism - the Zork authors were far too creative in the
"original" portions of Zork for them to have to "steal" any ideas.
Nowadays, lots of adventure authors (me included) just automatically
include mazes of "twisty little passages, all alike", trolls guarding
bridges, and so on (but preferably with new twists to the plot!) since
they've become part of the interactive fiction mindset, as it were.
Maybe some oldtimer could enlighten me as to whether Advent was such a
classic already when Zork was written for this to be applicable?
It should also be stressed that while Advent didn't have a real
parser, and could only understand two-word "sentences" ("TAKE FOOD",
"KILL DRAGON"), Zork/Dungeon made a really good attempt at
natural-language processing. In fact, many modern games have parsers
that are far inferior to the one in Zork.
>Eventually, Infocon hired some of the MIT students and also Bob Subnik.
Didn't these people *found* Infocom?
>Eventually, a version
>that was much smarter appeared in DECUS replacing the hacked-up one that had
>a better parser. This version has even been ported to MS-DOS. As far as
>I understand, it is fairly faithful to a popular "vintage" of the -10-based
>MDL version, but not the latest version available there.
This version is available from the comp.sources.games archives, I
think. A few years ago, somebody undertook the huge, thankless task of
translating the source (several hundred kB of spaghetti FORTRAN 66)
into C, and they did a very good job of it! This C version has been
ported to about every conceivable platform, including Macintosh. In
fact even in the Mac version, the leaflet in the letterbox still says
"No DECsystem should be without one" :-)
>Infocon changed the game in ways that are offensive to any seasoned player:
>
>They continued to enhance the parser in likely not-very-important ways, which
>isn't problematic
I found at least one important enhancement: Zork II (the Infocom version) allows you
to say "enter bucket" (any seasoned player knows why you would want to
do that!), but the Fortran version barfs on that - I was totally
baffled, having played the Infocom version first, and had to ask for
help - it turned out the earlier parser only recognized "embark" or
something like that, which is not evry logical.
>but they *broke* the game up into 3 parts merely to
>satisfy the requirement that each part could fit into a 64K CP/M system
>without swapping.
I think the requirement was without *disk* swapping - even after the
breakup, the program uses overlays (don't know if it's of code or of
data). Probably, the full game wouldn't have fit on one floppy disk on
those early CP/M systems.
>This "proscribes" parts of the game, and enforces where
>you start at part 2 and part 3, etc.
That's not very nice, no. But on the other hand, the original Zork
cave is almost too big to be playable...
>Moreover, they changed the game
>somewhat, adding and deleting features that where specific to the original
>and replacing them with features that in some people's opinions aren't
>consistent with the prose-style of the original Adventure and ZORK. (Both
>are similar in style, not particulars.)
But IMHO at least one of the additions was great: The puzzle with the
demon and the coloured glass spheres in Zork II is really beautiul -
IF at its very best! (I could go into details to motivate this, but I
see no reason to review Zork II so long after its release :-)).
>I understand that they continued development on a PDP-10 for these games,
>and that the development language became known as ZIL, later DDL.
For those of you reading this in alt.folklore.computers, ZIL was used
for all the later Infocom text adventures as well.
>Eventually, they brought out MS-DOS versions of these games, but they ran
>from paranoidly copy-protected disks with disk copy counts (you can't copy
>a copy, and an original can only be copied twice), not from a true
>MS-DOS system disk.
On the other hand, nowadays you can buy the "Lost Treasures of
Infocom" for ~$40, which contains Zork I/II/III and 17 other Infocom
games, with no copy protection whatsoever.
>Again, the 64K restriction was applied, so the
>PC versions are "compatible" with the CP/M ones.
Actually, all they ported was the Z-code (the code emitted by the ZIL
compiler) interpreter. The data files are identical for CP/M, MSDOS
and other platforms.
>Various people have broken into these disks, and floating around internet
>are MS-DOS files that run directly under MS-DOS of the three files in the
>"Zork Trilogy" as they call it, including solve files for all three. Looking
>at the solve files, I see that there is only faint resemblance to the
>faithful ZORK version which is also floating around the net, possibly in
>source form.
I beg to disagree. Most of the puzzles are identical, as are the parts
of the cave that weren't butchered when the game was split into three.
>Floating around the net is also a C-based version of Adventure that the
>authors were extremely careful to be faithful to the original. They point
>out a few bugs in the original, but in all other ways it's the same. There
>are even compatibility switches to handle certain quirks to be as compatible
>as anyone would want, etc.
A, yes, that's the one I was referring to above.
>Had the Infocon version of Zork been as faithful, more people would be
>complaining less about it. As it stands, it is perceived as a sleazy way
>to make money off of a college hack.
I may be but an inexperienced newbie, but this is actually the first
time I've ever heard this criticism. It seems more or less "everybody
else" (I suppose everybody who didn't first play the MDL version) tend
to view the Infocom Zork trilogy as great classics of IF.
>Since the files were taken, MIT
>did obtain a copyright on the program to prevent further misuse.
A copyright on which version? I'm asking because the Fortran sources
floating around on the net are all "(c) Infocom". And isn't "misuse" a
rather strong term - I've always thought the original authors of Zork
were involved in starting up Infocom and doing what they did to the
game.
Magnus Olsson | \e+ /_
Dept. of Theoretical Physics | \ Z / q
University of Lund, Sweden | >----<
Internet: mag...@thep.lu.se | / \===== g
Bitnet: THEPMO@SELDC52 | /e- \q
Andrew Goodridge
[Lots of back and forth discussion of ZORK and MIT and Infocom]
I'm on a MASSIVE Infocom kick right now; I'd LIKE to get the "Real" story.
That whole discussion about MIT maintaining copyrights and Infocom making
money off of a college hack and all was completely WRONG, and I haven't
even started my research in any amount yet.
I DO know that Infocom was FOUNDED by Several MIT Students, including Mark
Blank and David Lebling, so the whole copyright thing came from NOwhere.
My problem is my youth. I'm only 22; I was 7 or 8 when Zork was worked on.
I'm not very regretful; I got to see 16 million colors before I was 19.
But it means I'm starting at a disadvantage.
As for the locations of code and stuff, I've been looking into that as well.
This is what ARCHIE was created for. It's great.
So yes, if anyone was there or knows something accurately enough, I'd
like to know Infocom's story. For real.
Sergej Roytman
|>
|> Does anyone in this group remember MDL (muddle)? I was told that
|>the original Adventure was written in it. It seems that it was an
|>interactive fiction game language. Is this true? Also, I was told that
|>the Infocom text-based games were written in a language based on a
|>subset of MDL. Finally, if anyone has the original Adventure source (in
|>MDL) or anything else in MDL, I'd like to look at it.
|>
|> thanx,
|> Sam
|
|
|authors were extremely careful to be faithful to the original. They point
|out a few bugs in the original, but in all other ways it's the same. There
|are even compatibility switches to handle certain quirks to be as compatible
|as anyone would want, etc.
|
Any idea where it can be had?
|
|cjl
|
--
-----------------------------------------------------------------------
| ft...@engin.umich.edu | "... a stainless steel rat in the |
| (Sergej Roytman) | ferroconcrete wainscoting of Internet" |
-----------------------------------------------------------------------
Say no to four-line .sigs.
Charlie Gibbs
>Various MIT students wrote MDL and the game ZORK in it. It was their
"answer"
>to Adventure, and is somewhat more complex and difficult, and has some
>sections that are clearly "borrowed" from Adventure. For example, Adventure
>has a section where the room names are unique, but so similar, you can
easily
>get lost. You are in a twisty little maze of passages, all different is
>*not* quite the same as you are in a little twisty maze of passages, all
>different, etc. Zork has a similar region requiring the same fortitude to
>get through. However, it also has another area where they have a similar
>name, but are literally identical to trick you.
Adventure also has the maze of identically-named rooms; you
have to solve it to get the pirate's chest. You can win Adventure
without going into the "maze of twisty little passages, all
different" at all.
I got my hands on the PDP-11 source for both Adventure and
Dungeon and did a couple of ports myself (one to our mainframe,
whose bisync block-mode terminal I/O was a nightmare worthy of
a story in itself). Weeding out the DEC extensions (bitwise
operations and radix 50 especially) was lots of fun. :-p
Thanks for the history.
Charli...@mindlink.bc.ca
"I'm cursed with hair from HELL!" -- Night Court
Charlie Gibbs
(Magnus Olsson) writes:
>Actually, all they ported was the Z-code (the code emitted by the ZIL
>compiler) interpreter. The data files are identical for CP/M, MSDOS
>and other platforms.
Yup. I once wrote a program that pulled the data file for
Suspended off an MS-DOS disk. I transferred it to a CP/M disk and
played it with the CP/M Planetfall interpreter.
Charli...@mindlink.bc.ca
You are in a twisty maze of little menus, all alike.
Juergen Nickelsen
good...@husc8.harvard.edu (Andrew Goodridge) writes:
[...]
> My problem is my youth. I'm only 22; I was 7 or 8 when Zork was
> worked on. I'm not very regretful; I got to see 16 million colors
> before I was 19. But it means I'm starting at a disadvantage.
(Sorry, pet peeve:)
Where did you see 16 million colors? Not on *one* screen at a time, I
suppose, or I'd like to see that screen.
--
Juergen Nickelsen
Jonathan M Lennox
>In article <8em6K2C00...@andrew.cmu.edu> Samuel Roy Helwig <sh...@andrew.cmu.edu> writes:
>> Does anyone in this group remember MDL (muddle)? I was told that
>>the original Adventure was written in it.
>
>No, Adventure was originally written in Fortran. The original Zork was
>written in MDL.
>
>> It seems that it was an
>>interactive fiction game language. Is this true?
>
>Not really. MDL was a variant of Lisp, used by a small group at the MIT
>Laboratory for Computer Science (the Dynamic Modeling group) in the 70's.
>Many of its distinguishing features (better abstract data type support, in
>particular) eventually found their way into Common Lisp.
This obviously presents the question: is the original MDL source
available anyplace, and can it be translated into Common Lisp?
Another post on this group indicated that the MDL Zork had more rooms
and a better parser than the Fortran port--if this is true, I'd
certainly prefer to have the former.
Jonathan Lennox
jm...@cunixa.cc.columbia.edu
Anthony Shipman
>>Eventually, a version
>>that was much smarter appeared in DECUS replacing the hacked-up one that had
>>a better parser. This version has even been ported to MS-DOS. As far as
>>I understand, it is fairly faithful to a popular "vintage" of the -10-based
>>MDL version, but not the latest version available there.
>This version is available from the comp.sources.games archives, I
>think. A few years ago, somebody undertook the huge, thankless task of
>translating the source (several hundred kB of spaghetti FORTRAN 66)
>into C, and they did a very good job of it! This C version has been
>ported to about every conceivable platform, including Macintosh. In
>fact even in the Mac version, the leaflet in the letterbox still says
>"No DECsystem should be without one" :-)
Are you referring to the "cdungeon" program found in
comp.sources.games/volume12/cdungeon
It's History file says that it is translated from the Fortran but that
it has been superceded by Zork. ....
---------------
Please note that Dungeon has been superceded by the game ZORK(tm).
The following is an extract from the new product announcement for
ZORK in the September, 1980 issue of the RT-11 SIG newsletter:
"'ZORK: The Great Underground Empire - Part I' ...was developed
by the original authors based on their ZORK (Dungeon) game for
the PDP-10. It features a greatly improved parser; command
----------------
>That's not very nice, no. But on the other hand, the original Zork
>cave is almost too big to be playable...
>I beg to disagree. Most of the puzzles are identical, as are the parts
>of the cave that weren't butchered when the game was split into three.
>>Floating around the net is also a C-based version of Adventure that the
>>authors were extremely careful to be faithful to the original. They point
>>out a few bugs in the original, but in all other ways it's the same. There
>>are even compatibility switches to handle certain quirks to be as compatible
>>as anyone would want, etc.
>A, yes, that's the one I was referring to above.
????
>A copyright on which version? I'm asking because the Fortran sources
>floating around on the net are all "(c) Infocom". And isn't "misuse" a
>rather strong term - I've always thought the original authors of Zork
>were involved in starting up Infocom and doing what they did to the
>game.
cdungeon has .....
/*COPYRIGHT 1980, INFOCOM COMPUTERS AND COMMUNICATIONS, CAMBRIDGE MA. 02142*/
/* ALL RIGHTS RESERVED, COMMERCIAL USAGE STRICTLY PROHIBITED */
/* WRITTEN BY R. M. SUPNIK */
---------------------------------
So now I'm confused. What is the genealogy?
dungeon --> cdungeon --> Zork --> Zork I, II, III
or
dungeon --> (cdungeon = Zork) --> Zork I, II, III
or
dungeon --> cdungeon --> (Zork = Zork I) -->Zork II, III
or what?
--
Anthony Shipman "You've got to be taught before it's too late,
CP Software Export Pty Ltd, Before you are six or seven or eight,
19 Cato St., East Hawthorn, To hate all the people your relatives hate,
Melbourne, Australia, 3121 You've got to be carefully taught." R&H
Lupe Christoph
>(Sorry, pet peeve:)
Maybe he just went outside? :-P
--
| ...!unido!ukw!lupe (German EUNet, "bang") | Disclaimer: |
| lu...@ukw.UUCP (German EUNet, domain) | As I am self-employed, |
| suninfo!alanya!lupe (Sun Germany) | this *is* the opinion |
| Res non sunt complicanda praeter necessitatem. | of my employer. |
Charles Lasner
>
>Are you referring to the "cdungeon" program found in
> comp.sources.games/volume12/cdungeon
>
>It's History file says that it is translated from the Fortran but that
>it has been superceded by Zork. ....
>
>cdungeon has .....
>
>
>
>/*COPYRIGHT 1980, INFOCOM COMPUTERS AND COMMUNICATIONS, CAMBRIDGE MA. 02142*/
>/* ALL RIGHTS RESERVED, COMMERCIAL USAGE STRICTLY PROHIBITED */
>/* WRITTEN BY R. M. SUPNIK */
>
>
>So now I'm confused. What is the genealogy?
>
> dungeon --> cdungeon --> Zork --> Zork I, II, III
>
>or
>
> dungeon --> (cdungeon = Zork) --> Zork I, II, III
>
>or
>
> dungeon --> cdungeon --> (Zork = Zork I) -->Zork II, III
>
>
>or what?
I would like this explained also. As far as I'm concerned, there is only
one "true" ZORK, the MDL version. However, while it was under development,
various ripoffs of it appeared. Apparently cdungeon is a port or translation
of the Fortran version that aspires to be compatible with the 585 point version
of MDL ZORK which isn't the latest version. Moreover, the Fortran version
itself went through revisions and was originally a hacked-up version of
Adventure in Fortran appropriated to attempt to run the MDL ZORK's cave
description, without permission of MIT, which in turn led to MIT copyrighting
1980 MDL ZORK itself. Apparently Supnik, a known former DEC employee, who
in turn was responsible for converting the Fortran-10 sources of Advent into
the wimpier PDP-11 Fortran version (wimpier because the Fortran is wimpier;
he had little choice), evolved the Fortran code into something a little better
suited to play the 585 point ZORK, but still not quite as good as MDL ZORK
always was. If cdungeon is merely a port to C, so be it. In any case,
there is no other version of 616 point MDL ZORK to be had anywhere. The
ZORK trilogy is split into three contrived parts, and has additional
incompatible features, some of which are considered to have merit by certain
people, but clearly not totally agreed upon as improvements by all observers
for all changes. The consensus is that the splitting is an unacceptable
intrusion into the spirit of the game, and was merely done as an expediency
so each part can fit into the memory of 64K machines alongside an interpreter
of the Z code generated for that module of the game. Admittedly the parser
of Zork Trilogy may be as good or even slightly better than MDL ZORK, but this
is far outweighed by the split. Moreover, MDL ZORK' parser at the 616 point
version represents a somewhat better parser than the MDL ZORK parser for the
585 point earlier version, which is apparently the role model for all of these
other inferior versions.
cjl
Magnus Olsson
>In article <1992Oct1.1...@bohra.cpg.oz.au> a...@bohra.cpg.oz.au (Anthony Shipman) writes:
>>
>>Are you referring to the "cdungeon" program found in
>> comp.sources.games/volume12/cdungeon
>>
>>It's History file says that it is translated from the Fortran but that
>>it has been superceded by Zork. ....
>
>>
>>cdungeon has .....
>>
>>
>>
>>/*COPYRIGHT 1980, INFOCOM COMPUTERS AND COMMUNICATIONS, CAMBRIDGE MA. 02142*/
>>/* ALL RIGHTS RESERVED, COMMERCIAL USAGE STRICTLY PROHIBITED */
>>/* WRITTEN BY R. M. SUPNIK */
>>
>>
>>So now I'm confused. What is the genealogy?
[...]
>I would like this explained also. As far as I'm concerned, there is only
>one "true" ZORK, the MDL version. However, while it was under development,
>various ripoffs of it appeared. Apparently cdungeon is a port or translation
>of the Fortran version that aspires to be compatible with the 585 point version
>of MDL ZORK which isn't the latest version.
I think I can shed a little light on one small issue here:
The version known as 'cdungeon' is a relatively late addition. According
to the docs, it's an almost "literal" translation of the Fortran
version distributed as 'dungeon' - I think one of the few changes was
that the password check to enter GDT has been removed. Below is the
"HISTORY" file from a recent Macintosh port of cdungeon.
Magnus Olsson | \e+ /_
Dept. of Theoretical Physics | \ Z / q
University of Lund, Sweden | >----<
Internet: mag...@thep.lu.se | / \===== g
Bitnet: THEPMO@SELDC52 | /e- \q
History of the C Implementation of Dungeon
---------------------------------------
This version of dungeon has been modified from FORTRAN to C. The
original was written in DEC FORTRAN, translated from MDL. It was then
translated to f77 for UN*X systems, from which it was translated to C.
The C translation was done with the help of f2c, the FORTRAN to C
translator written by David Gay (AT&T Bell Labs), Stu Feldman
(Bellcore), Mark Maimone (Carnegie-Mellon University), and Norm
Schryer (AT&T Bell Labs).
I. From the original documentation...
To: Dungeon Players
From: "The Translator"
Subj: Game Information
Date: 8-OCT-80
This is the first (and last) source release of the PDP-11 version of
Dungeon.
Please note that Dungeon has been superceded by the game ZORK(tm). The
following is an extract from the new product announcement for ZORK in
the September, 1980 issue of the RT-11 SIG newsletter:
"'ZORK: The Great Underground Empire - Part I' ...was developed by the
original authors based on their ZORK (Dungeon) game for the PDP-10. It
features a greatly improved parser; command input and transcript
output files; SAVEs to any device and file name; and adaptation to
different terminal types, including a status line on VT100s. Note:
this is not the FORTRAN version that has been available through DECUS.
This version has been completely rewritten to run efficiently on small
machines - up to 10 times as fast as the DECUS version.
...ZORK runs under RT-ll, HT-ll, or RSTS/E and requires as little as
20K words of memory and a single floppy disk drive. The game package,
consisting of an RX01-format diskette and an instruction booklet, is
available from Infocom, Inc., P.O. Box 120, Kendall Station,
Cambridge, Ma. 02142."
ZORK(tm) is a trademark of Infocom, Inc. It is available for several
popular personal computers as well as for the PDP-ll.
VERSION HISTORY
II. DEC FORTRAN to f77 Conversion (17-nov-81)
The conversion from DEC FORTRAN to Unix f77 was done by Randy
Dietrich, Lynn Cochran and Sig Peterson. Much hacking was done to get
it to fit in the limited address space of a PDP-11/44 (split I/D).
Suffice it to say that by leaving out the debugging package and not
linking in the f77 i/o library they managed to get it to run.
III. PDP to VAX (dec-85)
Based on the work of Randy, Lynn and Sig, Bill Randle folded in the
full save/restore functions and the game debugging package (gdt) into
the pdp version to create a Vax/Unix version. This version also uses
f77 i/o, thus eliminating the extra speak and listen processes needed
on the pdp.
IV. Cleanup I (11-dec-86)
John Gilmore (hoptoad!gnu) cleaned up the source files by moving most
of the common declarations into include files and added comments from
the original (FORTRAN or MDL?) source. His efforts are greatly
appreciated.
V. Cleanup II (9-feb-87)
Bill Randle (bi...@tekred.tek.com) added the pdp dependencies back
into the Vax source files with #ifdefs in order to have just one set
of sources. Previously, there were two sets of source: one for the pdp
and one for the Vax. In addition, a shell escape of the form !cmd was
added and the wizard can enter the gdt without having to recompile the
source. Finally, a man page was generated, based on the dungeon.doc
file.
VI. f77 to C (11-mar-91)
Ian Lance Taylor (i...@airs.com or uunet!airs!ian) used the f2c
translator to generate C source code. The resulting code was modified
to remove the FORTRAN I/O library, to add simple more processing, and
to change the format of the database file. Andre Srinivasan
(an...@cs.pitt.edu) help test it. Jonathan Mark (uunet!microsoft!jonm)
made it work under MS-DOS and Microsoft C. Anthony C. Ard made it work
with the Macintosh and THINK C.
Steve McKinty - Sun ICNC
> The version known as 'cdungeon' is a relatively late addition. According
> to the docs, it's an almost "literal" translation of the Fortran
> version distributed as 'dungeon' - I think one of the few changes was
> that the password check to enter GDT has been removed. Below is the
> "HISTORY" file from a recent Macintosh port of cdungeon.
Speaking of GDT, what is/was the appropriate response? We found a copy
of Dungeon our University VAX in about 1981, but had no access to
sources (& none to the binary after the computer centre found out
about DUa0:[GAMES]. Luckily we had copied it elsewhere by then...)
After trying to guess at an answer to the GDT question for a while we
gave up and patched the image to remove the check, so I never discovered
what the right answer was.
Email if you don't want to give the game away
Steve
--
Steve McKinty
SUN Microsystems ICNC
38240 Meylan, France
email: smck...@france.sun.com BIX: smckinty
Tom Almy
>So now I'm confused. What is the genealogy?
Originally Dungeon was written in MDL.
I played a version in the late 1970's that was a translation into Fortran.
It was dated 18-JUN-78, and was distributed by DECUS. Compared to the MDL
version it claimed to lack the endgame, have a simple parser, and have
numerous bugs and spelling errors. It had 500 points.
In 1980 (I believe) a new version came out, this time with sources, that
had the endgame, the egg, the Bank of Zork, and the Puzzle Room added.
Maximum score was now 585 points. The game was then renamed Zork.
Infocom was apparently formed about this time to distribute commercially
to the fledgling home computer market. I had CP/M versions of their games,
for instance.
They rewrote the games (again) to use a small compact interpreter and a
database. (The Fortran is Spaghetti code). This made the program so it
would run on machines with little memory (PDP/11's, 8080's...) since the
database would be loaded as necessary from the (floppy) disk. The floppy
disk capacity on these systems was not great enough to put the entire game,
therefore they had to split it into three parts -- ZORK I, ZORK II, and
ZORK III. (IMHO, it probably would have fit into two games, but because it
doesn't really divide up well, they had to add to II and III to make them
stand on their own).
This new C port, is the 1980 Fortran version brute force converted to
C with a conversion program (this according to its documentation). Looking
at the code bears this out -- it is terrible C code, full of gotos! Quite
naturally it is the same as the old version.
--
Tom Almy
to...@sail.labs.tek.com
Standard Disclaimers Apply
Johnny Billquist
>Speaking of GDT, what is/was the appropriate response? We found a copy
>of Dungeon our University VAX in about 1981, but had no access to
>sources (& none to the binary after the computer centre found out
>about DUa0:[GAMES]. Luckily we had copied it elsewhere by then...)
>After trying to guess at an answer to the GDT question for a while we
>gave up and patched the image to remove the check, so I never discovered
>what the right answer was.
You cannot guess the answer, since the answer is dependant of the challenge.
There exists two version of DUNGEON from DECUS. One has a fixed password,
but is only available as a binary, and the EndGame is not yet implemented
in that version. The password was (if I remember correctly):
"SUPNIK,BARNEY,70524" (I might have the numbers somewhat wrong).
The final version from DECUS, with the EndGame gives you a challenge,
to which you shall answer anoter six-letter word. The algorithm is a
kind of crypto. Basically, it works like this:
Take the first letter in the challenge, create a word from it, but
putting each successive letter after the previous, until you get a six-
letter word. (If the challenge was "SUEYFX" for example, this second
word would be "STUVWX").
Put these two words above each other, and add the word "ECORMS" below
them both, giving you three words. Now do a letter for letter XOR
for each of the six letters. The resulting sex-letter word is the answer.
>Email if you don't want to give the game away
I have a program for the HP-41 and another one for the HP48 to solve
this, if enybody would be interested. The same crypto is used for the
INCANT spell.
--
Johnny Billquist || "I'm on a bus
CS student at Uppsala University || on a psychedelic trip
email: b...@minsk.docs.uu.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
Stu Galley
Copyright (c) Infocom, Inc. --- transcribed without permission
The History of Zork -- First in a Series
by Tim Anderson
In the beginning, back in the 1960's, DEC (Digital Equipment
Corporation) created the PDP-10, a medium-sized computer. The "10",
as it was called, became popular at many research installations, and a
great deal of software was written for it, some of which is still far
in advance of systems on more modern machines. At MIT's Artificial
Intelligence Lab, an operating system called ITS (Incompatible
Time-sharing System) was written for the 10. ITS was designed to make
software development easy. The designers of the system assumed that
it would have a small, knowledgeable, friendly group of users, so they
did not include any security features.
Around 1970, the ARPAnet was invented. ARPAnet made it possible for
researchers all over the country (indeed, all over the world) to
communicate with each other, and to use each other's machines. In
those halcyon days, access was unrestricted; you could get on from any
machine connected to the net, or by knowing an appropriate phone
number. Budding hackers from around the country soon discovered that
this made a wonderful playground. They also discovered that there
were some computers at MIT with some neat stuff on them and no
security -- anyone who could connect to the machines could log in.
Also around 1970, a language called MUDDLE (later renamed MDL) was
developed as a successor to LISP. It never succeeded in fully
replacing LISP, but it developed a loyal user community of its own,
primarily at MIT's Project MAC (now called the Laboratory for Computer
Science) and especially in the Dynamic Modelling Group (later the
Programming Technology Division). The Dynamic Modelling Group (DM),
in addition to its other accomplishments, was responsible for some
famous games. The first of these was a multi-player graphics game
called Maze, in which players wandered around a maze shooting each
other. Each user's screen showed the view of the maze that his or her
computerized alter-ego saw, updated in real time. Dave Lebling was
among those chiefly responsible (to blame?) for the existence of the
game.
The next game of note was Trivia (who says research labs aren't ahead
of their time?), an ongoing "can you top this" contest for the truly
crazed. Trivia, unlike Maze, could be played by network users, and
achieved wide popularity on the ARPAnet. Marc Blank wrote the second
version, and I maintained/hacked it; it was actually a legitimate test
of a database system the group used for a research project.
ln early 1977, Adventure swept the ARPAnet. Willie Crowther was the
original author, but Don Woods greatly expanded the game and unleashed
it on an unsuspecting network. When Adventure arrived at MIT, the
reaction was typical: after everybody spent a lot of time doing
nothing but solving the game (it's estimated that Adventure set the
entire computer industry back two weeks), the true lunatics began to
think about how they could do it better. Adventure was written in
FORTRAN, after all, so it couldn't be very smart. It accepted only
two-word commands, it was obviously hard to change, and the problems
were sometimes not everything one could desire. (I was present when
Bruce Daniels, one of the DM'ers, figured out how to get the last
point in Adventure by examining the game with a machine-language
debugger. There was no other way to do it.)
By late May, Adventure had been solved, and various DM'ers were
looking for ways to have fun. Marc Blank was enjoying a respite from
medical school; I had just finished my master's degree; Bruce Daniels
was getting bored with his Ph.D. topic; and Dave Lebling was heartily
sick of Morse code. Dave wrote (in MUDDLE) a command parser that was
almost as smart as Adventure's; Marc and I, who were both in the habit
of hacking all night, took advantage of this to write a prototype
four-room game. It has long since vanished. There was a band, a
bandbox, a peanut room (the band was outside the door, playing "Hail
to the Chief"), and a "chamber filled with deadlines." Dave played and
tested the game, saw that it was pretty awful, and left, to spend two
weeks basking in the sun.
Marc, Bruce, and I sat down to write a real game. We began by drawing
some maps, inventing some problems, and arguing a lot about how to
make things work. Bruce still had some thoughts of graduating, thus
preferring design to implementation, so Marc and I spent the rest of
Dave's vacation in the terminal room implementing the first version of
Zork. Zork, by the way, was never really named. "Zork" was a nonsense
word floating around; it was usually a verb, as in "zork the fweep,"
and may have been derived from "zorch." ("Zorch" is another nonsense
word implying total destruction.) We tended to name our programs with
the word "zork" until they were ready to be installed on the system.
By the time Dave got back, there was a (more-or-less) working game. It
probably wasn't as big as Adventure, and was certainly less than half
the size of the final version, but it had the thief, the cyclops, the
troll, the reservoir and dam, the house, part of the forest, the
glacier, the maze, and a bunch of other stuff. The problems were not
as interesting as those that came later: it took time for people to
learn how to write good problems, and the early parsers wouldn't
support complicated solutions anyway. What we had done right was all
in the "substratum." There was a well-defined (and easily-changed)
theory governing interactions among objects, verbs, and rooms. It was
easy to drop in new parsers, which happened frequently, since everyone
and his uncle tried his hand at writing a parser (Marc finally became
obsessed with it, and wrote the last 40 or 50 of them himself). And it
was easy to add new rooms, objects, and creatures (I won't discuss the
difficulty of adding new concepts yet).
Zork, like Adventure, survived only because it was played by people
outside the small community that developed it. In the case of
Adventure, this was possible because it was written in FORTRAN and
could run on practically any machine. Zork was written in MUDDLE,
which ran on only some PDP-10s. Its user community was the group of
"net randoms" that infested the MIT systems; remember that we had no
security at all at this time. DM had developed an active community
largely because of Trivia. Since Trivia was pretty dead by the time
Zork came along, there weren't many other things for the randoms to
do, so they hung around waiting for the next game. Early players of
Zork ranged from John McCarthy, the inventor of LISP (we actually have
a copy of the connectivity matrix that McCarthy used instead of a
map), to twelve-year-olds from Northern Virginia. No one ever
officially announced Zork: people would log in to DM, see that someone
was running a program named Zork, and get interested. They would then
"snoop" on the console of the person running Zork, and see that it was
an Adventure-like game. From there, it only took a little more effort
to find out how to start it up. For a long time, the magic incantation
was ":MARC;ZORK"; people who had never heard of ITS, DM, or PDP-10s
somehow heard that if they got to something called "host 70" on the
ARPAnet, logged in, and typed the magic word, they could play a game.
Although Zork in June 1977 was infinitely more primitive than, say,
Zork I, it still had pretty much the same flavor. The Flathead family
was represented, in the person of Lord Dimwit Flathead the Excessive,
ruler of the Great Underground Empire; and the official currency was
the zorkmid. Bruce was responsible for the purplish prose where these
were first mentioned.
Many of the details of the GUE were whimsical (if not silly), but we
weren't completely immune to reality. In those days, if one wandered
around in the dark area of the dungeon, one fell into a bottomless
pit. Many users pointed out that a bottomless pit in an attic should
be noticeable from the ground floor of the house. Dave came up with
the notion of grues, and he wrote their description. From the
beginning (or almost the beginning, anyway), the living room had a
copy of "US News & Dungeon Report," describing recent changes in the
game. All changes were credited to some group of implementers, but
not necessarily to those actually responsible: one of the issues
describe Bruce working for weeks to fill in all the bottomless pits
in the dungeon, thus forcing packs of grues to roam around.
The first major addition to the game, done in June 1977, was the river
section, designed and implemented by Marc. It survives largely
unchanged in Zork I, but illustrates very well the problems of
building reality. There were minor problems of consistency -- some
parts of the river were sunlit (and even reachable from outside), but
others were dark. The major problem resulted from the new concept
Marc introduced: vehicles. In the original game, there were rooms,
objects, and a player; the player always existed in some room.
Vehicles were objects that became, in effect, mobile rooms. This
required changes in the (always delicate) interactions among verbs,
objects, and rooms (we had to have some way of making "walk" do
something reasonable when the player was in the boat). In addition,
ever-resourceful Zorkers tried to use the boat anywhere they thought
they could. The code for the boat itself was not designed to function
outside the river section, but nothing kept the player from carrying
the deflated boat to the reservoir and trying to sail across.
Eventually the boat was allowed in the reservoir, but the general
problem always remained: anything that changes the world you're
modelling changes practically everything in the world you're
modelling.
Although Zork was only a month old, it could already surprise its
authors. The boat, due to the details of its implementation, turned
into a "bag of holding": players could put practically anything into
it and carry it around, even if the weight of the contents far
exceeded what a player was allowed to carry. The boat was two
separate objects: the "inflated boat" object contained the objects,
but the player carried the "deflated boat" object around. We knew
nothing about this: someone finally reported it to us as a bug. As
far as I know, the bug is still there.
from THE NEW ZORK TIMES Vol. 4 Nr. 2 - SPRING 1985
Copyright (c) Infocom, Inc. --- transcribed without permission
The History of Zork -- SECOND IN A SERIES
by Tim Anderson
When last seen, Zork(R) was a small game (probably slightly more than
half the size of the final mainframe version) that ran on one
computer. Although it was only six weeks old, and had never been
advertised, it had a relatively large user community from all over the
country. In some ways it was better than the classic Adventure at this
time, but mostly it was the next game to come along, and it wasn't
even the only contender.
The characters: MIT-DM, a PDP-10 running ITS; MDL (aka Muddle), a
language that ran only on PDP-10s; Marc Blank, Bruce Daniels, Dave
Lebling, and Tim Anderson, intrepid implementers; and assorted net
randoms.
July 1977 saw two major additions to the game, the last for several
months (we weren't exactly hired to write the thing, after all). The
first of these was another BKD special: Bruce didn't write much code,
but he was willing to design problems. We went to him, and asked for
a particularly nasty section; the result was the coal mine. His design
was originally nastier than the final implementation, since the maze
was just about as horrible as the original one in the game; it got
simplified due to popular demand. The problems were improving in
quality, and the coal mine maze was a late example of making things
hard by making them tedious.
The volcano section was Marc's second vehicle implementation, but is
perhaps more noteworthy for the loving portraits of Lord Dimwit
Flathead the Excessive that decorated the coin and stamp found in the
section. The river (see Part I) and volcano sections, in addition to
vehicles, required a better concept of time: both the boat and the
balloon moved more or less on their own, and the volcano required the
use of explosives and fuses. Marc added a clock daemon, which
processed a queue of events that would happen some fixed number of
moves later. This handled, in addition to the movement of the
vehicles, the fuse, the lantern burning out, and the mysterious gnomes
that occasionally appear. The first of these was in the volcano: if
the player got trapped in the upper reaches of the volcano by losing
his balloon, after a few moves a volcano gnome would appear and offer
freedom in exchange for a treasure. We were just being nice; most
players weren't allowed to save their games, so they had no way of
backing out if they made such a mistake. The gnome allowed them to
keep playing, albeit with no chance of getting all the points.
Even before the volcano section, we'd talked about a problem that
involved flying; Dave had a preference for something with an eagle,
and its aerie, but we could never figure out how to restrict things
enough -- it wouldn't do to have a parallel map of the game viewed
from the air. Once again, we worried about restraining a new concept,
so the balloon had no way of leaving the volcano. And once again we
were bitten by a new concept. When the player used the explosives in
the wrong place, and didn't get out of the way, he'd end up with
20,000 pounds (or was it tons?) of rock on his head. This made a
certain amount of sense in the underground section, but not out in the
forest.
No more sections were added to the game for several months after July,
but it continued to improve. In addition it finally moved to machines
other than DM, thus greatly expanding the number of players.
Although Muddle ran primarily on DM, a version for TENEX (the most
popular PDP-10 operating system on the Arpanet) had existed for some
time; the TENEX version could, with some minor modifications, run on
TOPS-20 as well. We finally succumbed to one of the requests for a
copy of Zork when we were given an account on a TOPS-20 machine on the
net. After we made the necessary software modifications, of course,
many copies could be made; a mailing list of Zork owners developed, so
They could get whatever updates appeared.
Although people could get runnable Zorks, they couldn't get sources.
We tried two approaches to protecting the sources (remember, there was
no protection of any sort on DM): they were normally kept encrypted;
and we patched the system to protect the directory where we kept the
sources (named CFS, for either "Charles F. Stanley" or "Computer
Fantasy and Simulation"). This worked pretty well, but was finally
beaten by a system hacker from Digital: using some archaic ITS
documentation (there's never been any other kind), he was able to
figure out how to modify the running operating system. Being clever,
he was also able to figure out how our patch to protect the source
directory worked. Then it was just a matter of decrypting the sources,
but that was soon reduced to figuring out the key we'd used. Ted had
no trouble getting machine time; he just found a new TOPS-20 machine
that was undergoing final testing, and started a program that tried
every key until it got something that looked like text. After less
than a day of crunching, he had a readable copy of the source. We had
to concede that anyone who'd go to that much trouble deserved it. This
led to some other things later on.
Players hadn't been able to save their Zorks because the method we
used at first took several hundred thousand bytes for each save, and
even on a time-shared system that was excessive. Marc, around this
time, invented a new way of saving that cut the size down to
something more reasonable, with the slight disadvantages that any new
rooms or objects added to the old game would break existing save
files, and that it never quite worked right anyway. However, it did
make it easier to play the game, and we still had the silly notion of
being nice to our users.
Fall '77 saw two major additions to the game, as Marc took another
break from medical school (yes, fans, he did graduate on time), and
Dave got into coding in a big way. The Alice in Wonderland section,
complete with its magic bucket and robot, was installed. The robot was
the first "actor," an object that could perform some of the same tasks
the player could. The style of address was familiar: "ROBOT, TAKE THE
CAKE." The implementation of this required another change in the
game's flow of control, and changes to anything else that one could
reasonably talk to.
The first version of fighting was added about the same time. Dave, an
old Dungeons and Dragons player, didn't like the completely
predictable ways of killing creatures off. In the original game, for
example, one killed a troll by throwing a knife at him; he would catch
the knife and gleefully eat it (like anything else you threw at him),
but hemorrhage as a result. Dave added basically the full complexity
of DD-style fighting, with different strengths for different weapons,
wounds, unconsciousness, and death. Each creature had its own set of
messages, so a fight with the thief (who uses a stiletto) would be
very different from a fight with the troll and his axe.
As a result of the purloined sources at DEC, a lunatic there decided
to translate Zork into FORTRAN. We had always assumed this would be
impossible: Muddle is very (oops, *very*) different from FORTRAN, and
much more complicated, and we'd used most of its features in designing
Zork. The guy who did it was mostly a hardware person, so perhaps he
didn't know what he was up against. At any rate, shortly after the
Great Blizzard of '78 he had a working version, initially for PDP-11s.
Since it was in FORTRAN, it could run on practically anything, and by
now it has.
Unfortunately, at some point in the preceding year we (no one will now
admit to suggesting the idea) had decided to change the name of the
game. Zork was too much of a nonsense word, not descriptive of the
game, etc., etc., etc. Silly as it sounds, we eventually started
calling it Dungeon. (Dave admits to suggesting the new name, but
that's only a minor sin.) When Bob the lunatic released his FORTRAN
version to the DEC users' group, that was the name he used. I'm sure
many people have noticed a curious similarity between the Dungeon game
they played on their friendly IBM 4341 and the Zork I they played on
their equally friendly IBM PC; now you know why.
Fortunately for us, a certain company (which shall remain nameless)
decided to claim that it had trademark rights to the name Dungeon, as
a result of certain games that it sold. We didn't agree (and MIT had
some very expensive lawyers on retainer who agreed with us), but it
encouraged us to do the right thing, and not hide our "Zorks" under a
bushel.
The next section that was added was intended to be the last: after a
player had accumulated all the points in the game, he could play the
End Game, designed largely by Dave. This became the section of Zork II
with the Dungeon Master, and at the time was certainly the most
involved, and hardest (as it should have been) thing in the game. The
implementation was, if anything, more involved than the problem. Less
than two months later, though, Marc had come up with something worse,
probably during a boring anatomy lecture. The bank section has
probably been fully deciphered by fewer people than anything else in
the game; even those who solve it on their own don't usually
understand what was going on. I can only say that it makes sense if
you understand it.
For some time, we'd been getting bug reports, fan mail, and
suggestions for new problems from all sorts of people. We were
beginning to run a little short on ideas anyway, and one of the ideas
we got was very good. During a lengthy dinner at Roy's, our favorite
Chinese restaurant, we worked out the details of the jewel-encrusted
egg, purple prose courtesy of Dave. Many people on the net had long
since solved the game, but went back in and did any new problems that
came along; one of them had played DD with Dave, and called him up
about a day after the egg was announced. "I've gotten the egg opened,
but I assume you losers have some nonsense where you do something with
the canary and the songbird. Dave, no fool, said "Cough, cough, ahem,
of course," and immediately went off and added the brass bauble.
The remaining puzzles, the Royal Zork Puzzle Museum and the palantirs,
were added in the late summer and fall of 1978. The puzzle was
designed (several times) primarily by Bruce, who in theory was back
trying to finish his dissertation. Finding the minimum number of moves
required to solve it was a popular pastime among dedicated Zorkers for
a while.
The last (lousy) point was a tribute to the final point in the
original Adventure, which involved leaving a particular object in a
particular room for no particular reason. When we first solved
Adventure in 1977, Bruce finally figured this out by using a
machine-language debugger on the running game (since Adventure was not
written in machine language, this was not easy). The major difference
between that and our version (a stamp worth One Lousy point) is that
it would be harder to find ours without the source of the game.
The last puzzle was added in February of '79. We (mainly I, at this
point) kept fixing bugs for almost two more years -- the last
mainframe update was created in January of '81. No new puzzles were
added because none of the implementers had time or inclination, and
because we had no more space available: at the time, we were limited
to a megabyte of memory, and we had used it all up. The first article
about Zork appeared in April of '79, and attracted a great deal of
interest; some of this may have been because we offered to give people
the game (if they didn't already have it), and gave them parts of the
sacred sources as well.
Infocom was incorporated in 1979 by various people from the DM group,
including Marc, Dave, and me. It was not founded to sell Zork; rather,
it was founded to give group members somewhere to go from MIT. Marc
and Joel Berez (both exiled to Pittsburgh) determined that it would be
possible to make Zork run on something cheaper than the $400,000
PDP-10, and the company eventually went along. See the next NZT for
further details.
In the meantime, we still get requests for hints on the mainframe Zork
(sometimes it's called Dungeon, and often it's on something other than
a PDP-10). The most recent request for a copy came in on April 1, but
I think it was serious.
[end]
David White
Thanks to all for the Bureaucracy (I KNEW those stamps were good for
something!) and Spellbreaker hints ('specially for the InvisiClues
walkthrough which someone provided.) (and incidentally, sorry if
"thank-you" messages are off-topic - still learning!)
=-=-= David =-=-=
--
The opinions expressed are not necessarily those of the University of
North Carolina at Chapel Hill, the Campus Office for Information
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internet: bbs.oit.unc.edu or 152.2.22.80
Charles Lasner
>I think I can shed a little light on one small issue here:
>
>The version known as 'cdungeon' is a relatively late addition. According
>to the docs, it's an almost "literal" translation of the Fortran
>version distributed as 'dungeon' - I think one of the few changes was
>that the password check to enter GDT has been removed. Below is the
>"HISTORY" file from a recent Macintosh port of cdungeon.
>
>History of the C Implementation of Dungeon
>---------------------------------------
>
>This version of dungeon has been modified from FORTRAN to C. The
>original was written in DEC FORTRAN, translated from MDL. It was then
>translated to f77 for UN*X systems, from which it was translated to C.
>The C translation was done with the help of f2c, the FORTRAN to C
>translator written by David Gay (AT&T Bell Labs), Stu Feldman
>(Bellcore), Mark Maimone (Carnegie-Mellon University), and Norm
>Schryer (AT&T Bell Labs).
That's a contradiction: Change it to:
This version of dungeon (aka zork) had been modified from a prior version
written in FORTRAN into C. The original was written in MDL, and then
translated to DEC FORTRAN, but not necessarily by a path that implies a
direct translation. (There are arguments about how the final DEC FORTRAN
version comes about and how it started. A "generous" description could be that
the DEC FORTRAN version was "modeled" after the MDL version which is
copyright (c) 1980 MIT and not available legally to the authors who were DEC
employees at the time of this "modeling" of the MDL version into the DEC
FORTRAN version.) The DEC FORTRAN version was then translated "all the way"
to f77 for un*x systems, from which it was translated into C.
cjl
Charles Lasner
>In article <1992Oct1.1...@bohra.cpg.oz.au> a...@bohra.cpg.oz.au (Anthony Shipman) writes:
>
>>So now I'm confused. What is the genealogy?
>
>Originally Dungeon was written in MDL.
Yes, and that version is the only true version with one game not split, good
parser, whole game, endgame, full features, and eventually 616 points.
>
>I played a version in the late 1970's that was a translation into Fortran.
>It was dated 18-JUN-78, and was distributed by DECUS. Compared to the MDL
>version it claimed to lack the endgame, have a simple parser, and have
>numerous bugs and spelling errors. It had 500 points.
Yes, that was the terrible version that appeared on VMS V 1.0, which was
still somewhat RSX-11 in drag. Internally, it was a hacked-up version of
ADVENT attempting to interpret the "cave" of MDL ZORK. Several revisions
appeared periodically of both MDL ZORK and this Fortran hacked-up version.
>
>In 1980 (I believe) a new version came out, this time with sources, that
>had the endgame, the egg, the Bank of Zork, and the Puzzle Room added.
>Maximum score was now 585 points. The game was then renamed Zork.
No, Zork is the original name of the -10/20 version. If you use the
"zork" command in any version, it responds with "at your service" shades of
PDP-10 AID. (eh?)
That very-much-improved Fortran version was slightly incompatible with the
MDL ZORK version in small ways (room directions off a little in spots) but
the disparity was much smaller.
Also, it's an announcement for the Infocom games to follow, and it's from
Infocom, not DEC, although Bob Supnik is clearly connected with the older
and this version; he was a DEC employee back then, and also now a manager
of Alpha.
>
>Infocom was apparently formed about this time to distribute commercially
>to the fledgling home computer market. I had CP/M versions of their games,
>for instance.
And at this time, "locking the barn after the horse was stolen" MIT copyrighted
the MDL ZORK version (c) 1980 MIT.
>
>They rewrote the games (again) to use a small compact interpreter and a
>database. (The Fortran is Spaghetti code). This made the program so it
>would run on machines with little memory (PDP/11's, 8080's...) since the
>database would be loaded as necessary from the (floppy) disk. The floppy
>disk capacity on these systems was not great enough to put the entire game,
>therefore they had to split it into three parts -- ZORK I, ZORK II, and
>ZORK III. (IMHO, it probably would have fit into two games, but because it
>doesn't really divide up well, they had to add to II and III to make them
>stand on their own).
Probably still has problems from its roots in being ADVENT Fortran code.
>
>This new C port, is the 1980 Fortran version brute force converted to
>C with a conversion program (this according to its documentation). Looking
>at the code bears this out -- it is terrible C code, full of gotos! Quite
>naturally it is the same as the old version.
>
>--
>Tom Almy
>to...@sail.labs.tek.com
>Standard Disclaimers Apply
cjl
Robert Blumenfeld
|> In <1992Oct1.2...@ukw.uucp> lu...@ukw.uucp (Lupe Christoph) writes:
|>
|> >nic...@cs.tu-berlin.de (Juergen Nickelsen) writes:
|>
|> >>In article <1992Sep30.1...@husc3.harvard.edu>
|> >>good...@husc8.harvard.edu (Andrew Goodridge) writes:
|>
|> >>[...]
|> >>> My problem is my youth. I'm only 22; I was 7 or 8 when Zork was
|> >>> worked on. I'm not very regretful; I got to see 16 million colors
|> >>> before I was 19. But it means I'm starting at a disadvantage.
|>
|> >>(Sorry, pet peeve:)
|>
|> >>Where did you see 16 million colors? Not on *one* screen at a time, I
|> >>suppose, or I'd like to see that screen.
|>
|> >Maybe he just went outside? :-P
|>
|> unbelievable... since 24 bit graphics (16 million colors) has been around
|> for a long time... But now it hits me...
|>
|> That would be 4096 x 4096 resolution... Pretty snazzy monitor!
|>
Gee, I just interpreted his claim in the way sociologists report that
by the age of 10 a typical American child has seen x-thousand murders
on TV. I mean, a hundred colors here, a hundred colors there -- it
all adds up.
-- Bob
David Messer
>nic...@cs.tu-berlin.de (Juergen Nickelsen) writes:
>
>>In article <1992Sep30.1...@husc3.harvard.edu>
>>good...@husc8.harvard.edu (Andrew Goodridge) writes:
>
>>> My problem is my youth. I'm only 22;
>>Where did you see 16 million colors? Not on *one* screen at a time, I
>>suppose, or I'd like to see that screen.
>
>Maybe he just went outside? :-P
Not likely: The human eye is only capable of resolving about
300-400,000 colors. Assuming he is in fact human of course. :)
--
Vote for Bush! | David Messer da...@lynx.mn.org -or-
He's been sick. | Lynx Data Systems ..!tcnet!lynxds!dave
Kenneth J Meltsner
In article <1992Oct2.1...@news.columbia.edu>,
las...@watsun.cc.columbia.edu (Charles Lasner) writes:
|>The consensus is that the splitting is an unacceptable
|>intrusion into the spirit of the game, and was merely done as an expediency
|>so each part can fit into the memory of 64K machines alongside an interpreter
|>of the Z code generated for that module of the game.
It wasn't the memory of the machines, but the disk space. The
original ZIL interpreters did include the ability to load (somewhat
compressed) text off of disk, as well as ZIL codes as you went from
room to room. Unfortunately, given the incredibly small disks of the
time on machines like the C-64, even putting the interpreter on a
separate disk would still mean that an unpartitioned full Zork would
require more floppy swaps than you could imagine.
The memory became a constraint later on as the parsers became more
sophisticated, more verbs were added, etc. I still remember the
impressive shift from 64K to 128K required memory -- the extra 64K
made a real difference for a couple of games. (Which ones? I recall
that Meretzkey's "A Mind Forever Voyaging" was the first 128K game,
but I could be wrong. They're all boxed in the attic now.)
As to Infocom and Dungeon and MIT:
(Several of) The Infocom founders were employed by MIT and wrote the
original MDL Zork as a response to Adventure and as something of an
experiment. MIT released the rights to Zork, based on its lack of
commercial value, and a FORTRAN version was hacked together, which
appears to be the source of the C version. Along the main line of
development of Zork, the Infocom founders formed the company (which
was intended to be a database company eventually, hence the name) and
wrote a Zork series broken up into chunks small enough to fit on the
dominant personal computers (Apples, etc.) of the time. Everything
grew from the Zork series, although the games became simpler and less
arbitrary to facilitate solution without "secret" knowledge, and
because most people had serious problems solving the "expert level"
Infocom games.
Infocom eventually killed itself off by pouring tons of bucks into
Cornerstone, which was its original reason for existence, and was
acquired by Activision. Activison never understood the niche text
adventure market and proceeded to push out mediocre and under-tested
adventures with increasing graphical content. Eventually, they pulled
the plug on the Cambridge operation.
Infocom at its peak put out literate and well-tested games of a
quality unmatched by its competitors or successors. A few approach
the effect of a good short story or novella; I'd suggest Trinity or
Bureaucracy for good examples of what can be done within the
Infocom-style adventure genre.
Disclaimer: I was in a club at MIT with some of the Infocom types.
Most of this based on dim recollections. Also, my wife beta-tested
several Infocom games.
===============================================================================
Ken Meltsner | melt...@crd.ge.com (518) 387-6391
GE Research and Development Center | Fax: (518) 387-7495
P.O. Box 8, Room K1/MB207 | Nothing I say should be attributed
Schenectady, NY 12301 | to my employer, and probably vice-versa
================ Materials and Manufacturing, World O' Stuff ==================
Lamar Owen
> >nic...@cs.tu-berlin.de (Juergen Nickelsen) writes:
> >>In article <1992Sep30.1...@husc3.harvard.edu>
> >>good...@husc8.harvard.edu (Andrew Goodridge) writes:
> >>> My problem is my youth. I'm only 22; I was 7 or 8 when Zork was
> >>> worked on. I'm not very regretful; I got to see 16 million colors
> >>> before I was 19. But it means I'm starting at a disadvantage.
> >>(Sorry, pet peeve:)
>
> >>suppose, or I'd like to see that screen.
>
> >Maybe he just went outside? :-P
>
> unbelievable... since 24 bit graphics (16 million colors) has been around
> for a long time... But now it hits me...
>
> That would be 4096 x 4096 resolution... Pretty snazzy monitor!
This is very true. But, even with a 4096x4096 screen, you still couldn't see
16 million colors. Why? The eye can only distinguish about 4 milllion colors.
So, those other 12 million are just useless baggage. Although using 24 bits
for color info is easy on the hardware and the programmer, these days, due to
IBM's success at pushing 8-bit bytes.
> ---Xeno
--
Lamar Owen, Systems Consultant, GE Lighting Systems, Hendersonville, NC
***********************************************************************
Opinions expressed herein are the author's and do not reflect policy
or opinions of the General Electric Company or its subsidiaries.
***********************************************************************
John E. Hinding
did studies where it was at around 24 bit that the eye couldn't tell the
difference. On a printed page the eye could tell a few million more
different shades. I believe the test involved printing text on shade
different from the background and seeing how far they had to go to not be
able to see the the text. The eye is better at seeing reflected light than
direct light mostly likely since humanity evloved by looking at reflected
light and not Tvs and monitors.
Gary L Snethen
>xe...@iastate.edu (Gary L Snethen) writes:
>>
>> That would be 4096 x 4096 resolution... Pretty snazzy monitor!
>This is very true. But, even with a 4096x4096 screen, you still couldn't see
>16 million colors. Why? The eye can only distinguish about 4 milllion colors.
>So, those other 12 million are just useless baggage. Although using 24 bits
>for color info is easy on the hardware and the programmer, these days, due to
>IBM's success at pushing 8-bit bytes.
Interesting observation...
However, with 24 bits, you can only represent 256 different values of
true grey... and I assure you that my eye can distinguish more than 256
shades of grey, so therefore either more bits are needed or the bits available
must be used more effectively to cover the entire spectrum that the human
eye can distinguish.
On a related note, are you covering the entire distinguishable intensity
range of the human eye? Your source of 4M colors may only be referring to
pigment colors. When the intensity of the source comes into play, you may
find that you can perceive up to 4M colors at any of hundreds of intensities.
A relatively easy test to see that your eye has more color resolution than
your 24 bit monitor would be to plot two adjacent colors (on a large scale)
that only differ by at most one intensity value in each of the R, G, and B
registers. When I do this for greys, they are perceivable... Some other
colors are not, however.
David Rowland
>xe...@iastate.edu (Gary L Snethen) writes:
>> In <1992Oct1.2...@ukw.uucp> lu...@ukw.uucp (Lupe Christoph) writes:
>> >nic...@cs.tu-berlin.de (Juergen Nickelsen) writes:
>> >>In article <1992Sep30.1...@husc3.harvard.edu>
>> >>good...@husc8.harvard.edu (Andrew Goodridge) writes:
>> >>[...]
>> >>> My problem is my youth. I'm only 22; I was 7 or 8 when Zork was
>> >>> worked on. I'm not very regretful; I got to see 16 million colors
>> >>> before I was 19. But it means I'm starting at a disadvantage.
>> >>(Sorry, pet peeve:)
>>
>> >>Where did you see 16 million colors? Not on *one* screen at a time, I
>> >>suppose, or I'd like to see that screen.
>>
>> >Maybe he just went outside? :-P
>>
>> Hmmm... First I was going to question why you suspected this was
>> unbelievable... since 24 bit graphics (16 million colors) has been around
>> for a long time... But now it hits me...
>>
>> That would be 4096 x 4096 resolution... Pretty snazzy monitor!
>
>This is very true. But, even with a 4096x4096 screen, you still couldn't see
>16 million colors. Why? The eye can only distinguish about 4 milllion colors.
>So, those other 12 million are just useless baggage. Although using 24 bits
>for color info is easy on the hardware and the programmer, these days, due to
>IBM's success at pushing 8-bit bytes.
>
one know the exact number of colours the human eye can see?
--
+---------------------+--------------------------------------------------+
| David Rowland | The British are using New Zealanders. They must |
| Datamark Intl Ltd | really mean bussiness ! |
| Wellington | - General Rommel During Northern African |
Tim Pierce
>4 Million Now. A few messages back, it was 350 000 colours. Does any
>one know the exact number of colours the human eye can see?
Eighty-seven.
--
____ Tim Pierce / "You are just naive and repressed because
\ / twpi...@unix.amherst.edu / penis envy is here and it's now and it's
\/ (BITnet: TWPIERCE@AMHERST) / all around you." -- Neal C. Wickham
Ron Dippold
>4 Million Now. A few messages back, it was 350 000 colours. Does any
>one know the exact number of colours the human eye can see?
It depends on the medium. I know that for many printed colors, you can
take a background of some 24-bit color value, then impose a shape on
it in which the color varies only in the lsb of one of the RGB
components, and people can observe the shape. For monitors, however,
there is less discrimination. I would tend to doubt the 350,000
colors, since the 256,000 available for VGA are so easily
distinguishable from each other.
--
This quote intentionally left blank.
Vadim Antonov
>one know the exact number of colours the human eye can see?
It depends on the level of H C OH in the blood -- there are
5 2
numerous documented cases when species of Homo Sapiens failed
to distinguish red from green shortly after sufficient intake of
an ethanol-containing liquid.
On the other side, some chemicals are known to sufficiently
improve the colour perception. LSD is arguably one of them.
Ever saw yellow-brown plaid sky with square sun? :-)
--vadim
Andrew Goodridge
This is getting way out of hand.
I tried to indicate how far we've come in computer technology.
When I said I've seen 16 million colors when I was a teenager, I meant
that computers had a pallette of 16 million relative colors to choose from.
Once, we had a choice of 2. Black and White. Or Black and Green.
That's all. We should have a huge discussion about REAL relevant things,
like, well, what's the most peripherals you've ever seen a private citizen
hook to his machine?
- Sketch
Karthik P Sheka
This is one of those times I wish I hadn't cut my Computer Graphics' class
on color. This is what I understand about it, though, from argueing with
the teacher and T.A. (With a little biology thrown in):
The human eye picks up only three colors, in different receptors (cones?):
red, green, and blue. All shading is done by the ratio of the receptors
with each other. There is a slightly larger amount of one of these types
of receptors than the other two. (I can't recall which one, but I think it
was green.)
When a computer creates a color image (usually) it does so by assigning a
certain number of bits to each of the primary colors. (again, red, green,
and blue.) VGA comes in 4 and 8 bit flavors, (2^4 == 16, 2^8 == 256) , so
the number of colors seen in VGA is either 16 or 256. Actually, VGA uses 8
bits, but I believe that they swap between two sets of four bits each, or
something, due to limitations on the memory throughput. (Add more memory to
a 16 color VGA card will usually give you a 256 color VGA card.)
Some of the nicer "super" VGA cards use 16 bits for color, giving 65536
colors. Since 2^16 cannot evenly be distributed among the three primary
colors, the extra bit is usually given to the primary that we can see more
shades of. (2^6 greens, 2^5 reds, 2^5 blues).
Most graphics workstations now come with 24 bit color. This gives 8 bits
of color for each of the primaries, or about 16 million colors. Some of
the more powerful graphics workstations now, and the graphics mainframes
and such come with 48 bit color, giving two bytes of color information to
each of the three primaries (giving 281 trillion colors).
We've already passed the point of diminishing returns, however. The most
significant difference is between 16 and 256 colors for most computer
applications. For image-processing, 16 bit color is usually enough, with
24 bit color used for serious tv-like color.
As for how many colors a person can see, its not a constant even for a
single person in a single one-hour period. If the colors being viewed are
very similar, say shades of green, the eye can pick up more colors within
those shades. This is because the cones in the eyes that pick up that
color get "tired", and the cones of the other colors have an easier time on
picking out the information that they can read.
No matter how many colors a flat computer display can have, however, it
will never be realistic enough to seem three-d. (I'm not counting stuff you
can do with polarized glasses or other pheriferals.) This is because, for
an object to seem three-d, it has to direct the light at a lot of different
angles, which is not possible on a flat screen.
This article turned out a lot longer than I initially expected. I guess
the moral is that you probably don't need a 24 bit video card, and to
invest in holographic displays.
//Karthik
Ignatios Souvatzis
Infocom developed much of the games on a PDP-11, i heard. Thus the Z-code
had a 12 bit format (maybe someone can correct me here).
Hm... PDP-11 is a 16bit machine. If Zcode has a 12bit format, it would
be related to the pdp8 and relatives, or maybe to the 36bit machined
(pdp10 and pdp20)
--
Paper mail: Ignatios Souvatzis, Radioastronomisches Institut der
Universitaet Bonn, Auf dem Huegel 71, D-5300 Bonn 1, FRG
Internet: so...@babsy.mpifr-bonn.mpg.de igna...@cs.uni-bonn.de
J A Stephen Viggiano
>16 million colors. Why? The eye can only distinguish about 4 milllion colors.
>So, those other 12 million are just useless baggage. Although using 24 bits
>for color info is easy on the hardware and the programmer, these days, due to
>IBM's success at pushing 8-bit bytes.
All this assumes optimal quantization, which our CRT display subsystems
certainly do not have. No digital display system does.
In order to properly represent natural color scenes (eg., scanned in
photographs), it is necessary to use *at least* 7 bits per channel. This is
easy to prove, as the eye can resolve approximately 100 levels of gray alone.
In order to avoid tonescale aliasing, at least 100 levels of gray must be
provided. This is conveniently accomplished with 7 bits; 2 ** 7 = 128. The
additional bit per channel is necessary to allow for multiple quantization,
as well as artifacts which are introduced as you allow multiple dimensions
(i.e., color images as opposed to monochrome).
Seven bits is barely sufficient for monochrome, and eight bits are preferred.
For color images, we need three planes, not just one, so 21 bits are
necessary. Those of you with true color systems, capable of displaying
24-bit color, might want to try a little experiment. Start with a good
quality natural color image, with a full depth of 24 fully-populated bits
per pixel. Quantize the image to 21 bits per pixel, and compare it to the
original version. There should be little, if any, discernable difference. Now
quantize it to 18 bits per pixel, and compare it again. You'll notice false
contours (they show up readily in skin and sky); these give the picture a
paint-by-numbers appearance. The effect is even more pronounced at 15 bits
per pixel, which allows 5 bits per plane.
This experiment is easy to do in Adobe Photoshop on the Macintosh, but you'll
need a 24-bit display system to do it. Starting with a good full-color scene,
perhaps one of the demonstration images they provide, verify that all levels
are populated, at least in margin, by looking at the Red, Green, and Blue
histograms under Image/Histogram. Then use the "Posterize" option to
perform the quantization -- first to 128 levels (7 bits), then to 64 levels
(6 bits), and finally to 32 levels (5 bits).
Those with eight-bit display systems can verify at least the first assumption,
that the eye can resolve seven bits' worth of lightness, by using a monochrome
image. Take a good black-and-white picture, with all or nearly all levels
occupied. Again, this can be verified using a histogram. Lop off the low
order bits, one at a time. If you have Photoshop, this can be done using
the Posterize tool. You should start seeing the contours at 6 bit (64 level)
quantization for most images. It works best on images which have smooth
transistions from light to dark -- a digitally-generated gradation can
help you see the results. Be sure your monitor is set to 256 grays before
you start.
The only reason some people are satisfied with 8-bit color mapped color
displays, such as VGA, is that they haven't worked with true color systems,
such as TARGA, VISTA, or 32-bit Quickdraw, or they're doing things such as
business graphics, which can use a small pallette of colors. For natural
color scenes, 24 bits per pixel is baseline performance.
Steve Viggiano, A.B., Sc.M., M.Stat.
Senior Imaging Scientist
Rochester Institute of Technology Research Corporation
Mr KH Chung
> In article <1992Oct8.0...@datamark.co.nz> da...@datamark.co.nz (David Rowland) writes:
>
> >4 Million Now. A few messages back, it was 350 000 colours. Does any
> >one know the exact number of colours the human eye can see?
>
> Eighty-seven.
The human eye can't really distinguish that many colours, it only has red
blue and green receptors. It can, however, readily distinguish some 111
shades of grey (you can find it in some old article in Science xy, a now
non-existent magazine that used to be published by the AAAS).
Lamar Owen
> In <Xs76RB...@lorc.UUCP> lo...@lorc.UUCP (Lamar Owen) writes:
> >xe...@iastate.edu (Gary L Snethen) writes:
> >> That would be 4096 x 4096 resolution... Pretty snazzy monitor!
> >This is very true. But, even with a 4096x4096 screen, you still couldn't se
> >for color info is easy on the hardware and the programmer, these days, due t
>
> Interesting observation...
>
> However, with 24 bits, you can only represent 256 different values of
> true grey... and I assure you that my eye can distinguish more than 256
> shades of grey, so therefore either more bits are needed or the bits availabl
> eye can distinguish.
Also an interesting observation. The eye, due to its dual nature, is very
sensitive to intensity variations in the GREY realm. Why? Due to the splitting
of the retina into cones and rods. If I am not mistaken, cones perceive hue
mostly, and rods perceive intensity. Now, for survival, it is important to
be able to distinguish an object even in low light levels. This either implies
a logarithmic scaling of intensity, or a generally better resolution of
intensity. Note that, at low light levels, everything is grey. Very little
color, since the cones don't do as well in low light.
In fact, the eye is more sensitive to some color frequencies than others. I
do not remember exactly which right at this moment, but the very act of
color combining in a TV set makes use of this property to get the best
possible perceived chroma resolution. Acckk! I wish I could remember my
chroma bandpass filter gain ratios! (NTSC, of course. PAL uses a different
ratio set because of the different modulation technique).
Note also that the eye doesn't really use a primary color model for sight. As
far as the eye is concerned, there is only a frequency continuum, not three
primaries. Although, if you look at a color spectrum, the three traditional
primaries are by far the most noticeable colors. How then does the combination
of RGB produce such a wide range of color? Well, in this case a process which
is normally not ever desired produces a desireable effect: Intermodulation
distortion allows RGB devices (or CYMK) to emulate a real color picture. You
combine the three primary frequencies in various ratios, and you end up with
some very complex intermod products. However, an intermod white isn't quite as
WHITE as a _real_ white, which would be an even frquency distribution from red
to blue in real light. However, the phosphors in most CRT's are wideband
enough to cause the intermod to nearly spread across the whole spectrum.
So, to really produce real color, you would need more than just RGB. The CYMK
system is closer--with 65535 shades of grey available. In fact, CYMK can be
fit into 24 bits by noting which color the eye is the most sensitive to.
Now, the possible combinations of CYMK would, to an extent overlap. In fact,
there are lots of overlap. By reducing the matrix to the eye's real color
range, a true color system could be built that would match the eye's response
exactly. Basically, your pixel bit values would point to the proper color in
the palette of the eye's possible colors. Now, all we need is a largish ROM
and a 32-bit RAMDAC to get what we want out of 4 million colors. This
4 million color figure was quoted from a doctor.
David H. Thornley
>xe...@iastate.edu (Gary L Snethen) writes:
>> In <Xs76RB...@lorc.UUCP> lo...@lorc.UUCP (Lamar Owen) writes:
>> >xe...@iastate.edu (Gary L Snethen) writes:
>
>Also an interesting observation. The eye, due to its dual nature, is very
>sensitive to intensity variations in the GREY realm. Why? Due to the splitting
>of the retina into cones and rods. If I am not mistaken, cones perceive hue
>mostly, and rods perceive intensity. Now, for survival, it is important to
>be able to distinguish an object even in low light levels. This either implies
>a logarithmic scaling of intensity, or a generally better resolution of
>intensity. Note that, at low light levels, everything is grey. Very little
>color, since the cones don't do as well in low light.
>
talking about. Cones are used for detail vision in color at medium to
high light levels; rods are used for undetailed vision in black-and-white
at low light levels. If you can easily see colors, your rods probably
aren't contributing much to your vision. What you see as gray at higher
light levels is basically information from cones.
>In fact, the eye is more sensitive to some color frequencies than others. I
>do not remember exactly which right at this moment, but the very act of
>color combining in a TV set makes use of this property to get the best
>possible perceived chroma resolution. Acckk! I wish I could remember my
>chroma bandpass filter gain ratios! (NTSC, of course. PAL uses a different
>ratio set because of the different modulation technique).
>
Cone cells come in three varieties, sometimes called red, green, and blue,
but the red and green are actually pretty close to each other in the
general area of orange and yellow, and they aren't real fussy about what
frequencies they'll detect. Rods work best in greenish-blue, and so red
things look particularly dark at night. Effectively, the cones can be
fooled by any three colors into seeing almost any possible color, although
some combinations are more efficient than others. RBG is a good choice;
although it obviously cannot match any possible spectrum, it can simulate
the effects very well for the human visual system, since the eye can only
sample three frequencies (two in cats, four in bees, it varies among
species). Of course, beings with different visual systems will not see
video screens, paintings, etc., in a different way.
We covered the number of possible colors only briefly, and I don't remember
it. One interesting point is that the eye can differentiate far more
colors than it can recognize; i.e., two shades might look the same when
viewed separately, but might be easily distinguishable when together.
DHT
ObIntFict: I had real problems playing Deadline because the rooms were so
undetailed. A room would have a bed, a table, and a chair, each totally
without components. I realize that this means that searching rooms in
detail is not productive, but it ruined the image for me.
David Matiskella
>
> xe...@iastate.edu (Gary L Snethen) writes:
> > In <Xs76RB...@lorc.UUCP> lo...@lorc.UUCP (Lamar Owen) writes:
> > >xe...@iastate.edu (Gary L Snethen) writes:
> > >> That would be 4096 x 4096 resolution... Pretty snazzy monitor!
> > >This is very true. But, even with a 4096x4096 screen, you still couldn't se
> > >16 million colors. Why? The eye can only distinguish about 4 milllion colo
> > >So, those other 12 million are just useless baggage. Although using 24 bits
> > >for color info is easy on the hardware and the programmer, these days, due t
> > >IBM's success at pushing 8-bit bytes.
> >
> > Interesting observation...
> >
> > However, with 24 bits, you can only represent 256 different values of
> > true grey... and I assure you that my eye can distinguish more than 256
> > shades of grey, so therefore either more bits are needed or the bits availabl
> > must be used more effectively to cover the entire spectrum that the human
> > eye can distinguish.
>
colors until the eye couldn't tell a shade one unit higher in one component
apart. The easy way to prove this is look a a 24bit picture under vga,
hicolor, and in 24 bit mode. If the pictures don't look identical then the
added color inforamtion is valuable.
When I took psychology we spent a descent amount of time of the eye and
how it works. The truth is that no one is really sure with some favoring
the rgb method and others faving a method which two types of cone which
dectect the intensity of one of two colors.
Dik T. Winter
A good article, but I have a bit more information:
> RBG is a good choice;
> although it obviously cannot match any possible spectrum, it can simulate
> the effects very well for the human visual system, since the eye can only
> sample three frequencies (two in cats, four in bees, it varies among
> species).
This is one point. It appears that some human eyes can view four frequencies.
There appear to be two variants of the green detecting cones (with only a
slight variation in the frequeny). Some people have only one variant, but
some (mostly women) have both.
Another thing is that color-blindness does not only disable one to
distinguish two colors, but might also enable one to distinguish two
other colors! A well known (amongst some people) example is in a fairly
standard color-blindness test. The victim is shown figures consisting of
different colored circles. The victin should tell what digit he is seeing,
if any. For one of the examples a non-color-blind person will not see
anything, but a red-green color-blind person will see a digit.
This is all from a local paper a few months ago; a human perception
knowledgable person will probably know more about it.
--
dik t. winter, cwi, kruislaan 413, 1098 sj amsterdam, nederland
home: bovenover 215, 1025 jn amsterdam, nederland; e-mail: d...@cwi.nl
Michael Greim
Seems I missed this discussion until now.
In article <1992Sep30....@pollux.lu.se>, mag...@thep.lu.se (Magnus Olsson) writes:
= In article <1992Sep30....@news.columbia.edu> las...@watsun.cc.columbia.edu (Charles Lasner) writes:
[...]
= >This "proscribes" parts of the game, and enforces where
= >you start at part 2 and part 3, etc.
=
= That's not very nice, no. But on the other hand, the original Zork
= cave is almost too big to be playable...
Hm, once upon a time I did not even need to consult the maps to walk around.
=
= On the other hand, nowadays you can buy the "Lost Treasures of
= Infocom" for ~$40, which contains Zork I/II/III and 17 other Infocom
= games, with no copy protection whatsoever.
I have been on the lookout for Infocom adventures for quite some time now.
In fact, last saturday I bought "Leather Godesses of Phobos" at 19.90 DM
(~ 13 US $) at a shop in Trier.
Does anyone have the address of the firm that sells these "Lost Treasures
of Infocom" in plain @-mail notation (how very antique:-) ? I'd like
to write and order a packet. A friend and I have several games, some
for C64, some for Amiga, some for PC, but there are others which we
still have not seen here in Germany yet.
-mg
--
------
Michael Greim e-mail : m...@cs.uni-sb.de or : ...!uunet!unido!sbsvax!mg
@-mail : Sudstr. 22, 6602 Dudweiler, W.Germany
.-. .-. .-. voice : +49 681/302-2434
( X )( __) As the Sun pulls away from the shore, and our boat sinks
\_/ \_/ \_/ slowly in the west ... --- Spike Jones
Lamar Owen
> This experiment is easy to do in Adobe Photoshop on the Macintosh, but you'll
> need a 24-bit display system to do it. Starting with a good full-color scene,
> perhaps one of the demonstration images they provide, verify that all levels
> are populated, at least in margin, by looking at the Red, Green, and Blue
> histograms under Image/Histogram. Then use the "Posterize" option to
> perform the quantization -- first to 128 levels (7 bits), then to 64 levels
> (6 bits), and finally to 32 levels (5 bits).
I tried this on my 40 plane Apollo system. (Actually, the Apollo board
is 40 bit, but the docs say "plane" to mean Bit-Plane instead of color
plane.) A Custom program generated a plasma cloud fractal, another custom
program did the "posterizing". The transition from 24 bit to 23-bit was not
noticeable. 23 to 22 was not noticeable. 22 to 21 was noticeable. The
color mapping at 24 bit was (r,g,b) 8,8,8 bits. 23 was 8,8,7; 22 was 7,8,7;
and 21 was 7,7,7.
> The only reason some people are satisfied with 8-bit color mapped color
> displays, such as VGA, is that they haven't worked with true color systems,
> such as TARGA, VISTA, or 32-bit Quickdraw, or they're doing things such as
> business graphics, which can use a small pallette of colors. For natural
> color scenes, 24 bits per pixel is baseline performance.
Or even the 40-bit Apollo system. It seems to be forgotten these days.
> Steve Viggiano, A.B., Sc.M., M.Stat.
> Senior Imaging Scientist
> Rochester Institute of Technology Research Corporation
I find it very intriguing the levels of expertise available in all sorts of
fields in a.f.c!
:-) :-)
Lamar Owen
> That's all. We should have a huge discussion about REAL relevant things,
> like, well, what's the most peripherals you've ever seen a private citizen
> hook to his machine?
Well, I've got them all beat. I just connected a machine (VERY briefly) to the
Internet. My IBM-PC, that is, running PC/IP. Actually, it's not MY IBM-PC,
but one at work. I don't own an IBM-PC--I own a real PC--AT&T UNIX-PC.
Haven't you heard the old joke? "Mainframes: the most expensive peripherals
money can buy for the PC." On the Internet, there are over a million
intelligent "peripherals".
My IP address was 3.62.4.250 for a small time. This is within GE, so access is
limited to SMTP e-mail.
Actually, my machine is still connected physically to Internet--just running
Novell's IPX right now.
Oh, you meant *local* connections... Oh well...
I can't touch that one--Channel 1 BBS or EXEC-PC BBS probably take the cake,
with over 100 modems on EXEC-PC (I believe also over 100 PC's in a network),
and 70+ modems and PC's for Channel 1. Oh, but you meant a *single* computer,
not a network... Hmmm... Well, the Apollo Domain system blurs that distinction,
being that memory is shareable amongst machines, processes are shareable,
video is shareable (ever seen net_bounce on an Apollo? Bounces an object across
multiple workstation's screens), the mouse is shareable (move your mouse cursor
to another workstation and open a window there). Shoot, even X workstations
can do some of this, by changing the DISPLAY environment variable (or using
a command line -display parameter)).
Well, for a single computer, Eric Greene (of Greene Machine BBS fame) had a
PDP 11/23 with 16 modems, four floppy disks, 8 terminals, and two printers
for a hobby system.
> - Sketch
Charles Lasner
>
>Well, for a single computer, Eric Greene (of Greene Machine BBS fame) had a
>PDP 11/23 with 16 modems, four floppy disks, 8 terminals, and two printers
>for a hobby system.
Not good enough. I wrote a PDP-8-based message-switching system with filing
capabilities, etc. that serves 40 logical tasks including console terminal,
several line-printers, paper-tape reader/punch, and 4 banks of 8-channel
multiplexed serial line adaptors. Baud rates to 19,200 were possible on
all serial lines, but most were set to 1200 baud, since that was the
prevailing modem speed of the day. Some were defined as output-only to
send messages to other systems, and a few were input-only to receive messages
from other systems. Two such systems were in continuous usage, so some lines
were interconnected so the systems had access to each other's data. Each
machine had 2 hard disks, all removable so there was no need for an additional
device for backup. The usual configuration had about 24 terminals or modems
connected to terminals, the rest were the lines designated as one-way, but
all could be reconfigured as necessary.
Terminals came in two flavors: normal full-duplex, and buffered. The buffered
mode was used by other systems that followed various industry-standard
buffered terminal conventions when accessing the -8's data. The full-duplex
terminals were the so-called "operator's" terminals which could manipulate
the system's queues, etc., and could cancel output in progress, etc., as
well as delete files. All terminals could acquire detailed directories of
the files, as well as examine the message queues. The master PDP-8 console
was the only place certain "privileged" operations could be initiated to
reconfigure the system.
While I never had all of the terminals in the home version, I did have the
complete muxes as well as all of the incidentals (printers, readers, etc.),
and would debug using a few buffered terminals hooked at random to one or
two of the 32 available RS-232 connectors on the combined mux access panels.
cjl
John Francis
>not a network... Hmmm... Well, the Apollo Domain system blurs that distinction,
>being that memory is shareable amongst machines, processes are shareable,
>video is shareable (ever seen net_bounce on an Apollo? Bounces an object across
>multiple workstation's screens), the mouse is shareable (move your mouse cursor
>to another workstation and open a window there).
Thank you for your kind words for our systems. Unfortunately, you are incorrect.
Memory, processes, etc. are no more sharable than they are on any network of Unix
workstations connected to a LAN.
What the Apollo Domain network offered was a real network-wide file system that
was always there (you didn't need to explicitly mount remote disks), and had the
necessary primitives to make read/write remote file access usable without the
problems that multiple independent write attempts cause on some other systems.
The net_bounce demo program makes clever use of the Network Computing Services
facilities to coordinate the display of an object between several cooperating
processes. The mouse moving between screens was only possible on a project
that I don't believe ever made it to the product line - multiple display heads
on a single workstation.
A modern workstation with the Andrew File System, Posix threads, and the OSF
Distributed Computing Environment can do most things that the Apollo systems
could do. The major distinction is that Apollo has had this stuff for years!
--
John Francis jo...@apollo.hp.com
with 9 cats to feed, I don't have time to think up a clever .sig
David O. Dodge
>js...@rc.rit.edu (J A Stephen Viggiano) writes:
>> The only reason some people are satisfied with 8-bit color mapped color
>> displays, such as VGA, is that they haven't worked with true color systems,
>> such as TARGA, VISTA, or 32-bit Quickdraw, or they're doing things such as
>> business graphics, which can use a small pallette of colors. For natural
>> color scenes, 24 bits per pixel is baseline performance.
>
>Or even the 40-bit Apollo system. It seems to be forgotten these days.
Wasn't there an 80-bit version of that system also?
-Dave Dodge/dod...@wam.umd.edu
Stu Galley
(c) 1985 Infocom, Inc.
The History of Zork -- The Final (?) Chapter: MIT, MDL, ZIL, ZIP
by Stu Galley
Special To The New Zork Times
The year: 1979. As Tim Anderson has recounted in previous
installments in this series, Zork was one large computer game, about a
megabyte in size -- as large as it could be and still fit in its
original home, a DECsystem-10. Marc Blank and Dave Lebling designed
and wrote the program, with the help of Bruce Daniels and Tim. They
had met and worked together in a research group at M.I.T., and now the
group was losing valuable talent through graduation and the lure of
"the real world." Several members of the group believed that they
could still produce outstanding computer-based products in almost any
category -- from programming languages like MDL (an important
influence on modern Lisp) to data bases, electronic mail and
artificially intelligent systems -- if only centrifugal force didn't
separate them.
The problem: What sort of product could the group work on together,
and to whom could they sell it? As early as 1976, they had discussed
the potential marketability of various computer games that had been
designed or implemented by group members just for fun. Now their
attention was focused on various potential products based on
mini-computers, some involving custom hardware as well as software.
The group was ignoring the potential of a mass market for
micro-computers, not only from lack of experience with them (the
group's unofficial motto is "We hate micros!") but also from serious
concerns about software piracy.
Joel Berez had graduated from the group and was working in his
family's business in Pittsburgh. Marc had finished medical school
(and moonlighting on Zork development) and was starting his medical
residency in Pittsburgh. These two had long been friends, and they
liked getting together for a Chinese dinner and conversation.
One topic of conversation was "the good old days" at M.I.T., and one
reason that the old days were good was Zork. They wished that Zork's
wonderfulness (or "taste and winnage" in M.I.T. jargon) could somehow
be brought to more people. But very few people had access to the
large computers that could run Zork. More and more people were
beginning to buy personal computers -- like the Radio Shack TRS-80
Model I or the Apple II -- but those computers were too small to run
Zork. Or were they?
Joel and Marc began some seat-of-the-pants design work (much of it on
Joel's parents' coffee table) on how much Zork could be compressed,
and how to do so in a flexible way to allow for different,
incompatible personal computers in the future. They considered using
available "portable" tools for programming, like UCSD Pascal, but it
soon became clear that Zork had too much text in it. (Keep in mind
that a standard personal computer at this time came with 16K bytes of
memory and no disk drive.) They finally concluded that, by inventing
a programming system specifically for Zork, they could fit about half
of it into a computer with 32K bytes of memory and one floppy-disk
drive.
Meanwhile, the group at M.I.T. was in the process of forming a
corporation -- choosing "Infocom" as the name least offensive to
everyone -- and searching for a project that would quickly produce a
product to start generating income for the company. Among the
projects they considered were systems for keeping track of documents,
handling electronic correspondence, and processing text. When Zork
was added to the list of possibilities, Joel and Marc worked
intensively during the summer and autumn creating the programming
tools for their design. And they had to work for IOUs, since the
company treasury -- which started with only $11,500 -- could afford to
pay only for the hardware they needed at the time.
The key to their design was an imaginary computer chip called the
"Z-machine." This chip would be able to run Zork (or at least part of
it) if the program were coded in a special, very compact language.
Then the design called for each personal computer to have a program
(called a Z-machine Interpreter Program or ZIP) that would interpret
the special Z-machine language and make the computer act the same way
that a real Z-machine would. In order to get Zork written in this
special language, another language was invented, called Zork
Implementation Language (ZIL), similar in many ways to MDL. Marc
built a two-stage translator program that would translate a ZIL
program, first into an assembly language and then further into the
Z-machine language. He also built a ZIP so that a DECsystem-20 could
emulate the Z-machine.
There was still the problem of cutting Zork in half. Dave examined
his complete map of Zork and drew a boundary around a portion that
included about 100 or so locations: everything "above ground" and a
large section surrounding the Round Room. The object was to create a
smaller Zork that would fit within the constraints established by the
design of Joel and Marc. Whatever wouldn't fit was to be saved for
another game, another day.
In the process of being converted from MDL into ZIL, the program
became "cleaner" and friendlier. The geographies of the maze and the
coal mine were simplified so that the connections were less arbitrary,
and in other places complexity was removed whenever it didn't serve a
justifiable purpose. For example, there was originally a barrel
sitting near the top of Aragain Falls, but it was just a red herring;
its only purpose was to lure unsuspecting adventurers inside and carry
them over the falls to destruction. The Rainbow Room had its name
changed to On the Rainbow, and that meant removing the silly joke
about Rockefeller Center and the NBC Commissary. Since the Land of
the (Living) Dead (the word "Living" was removed in order to fit the
name on the status line) no longer led to the stairway where Zork III
later began, the crystal skull (a brand-new treasure) was put there
instead.
By late 1979, Joel and Marc had both moved back to Boston. Joel had
been elected president of Infocom and started business school, and
Zork I was shaping up as lnfocom's first product. Zork I first saw
the light of day on a DECsystem-20 on which the company was renting
time, then on the PDP-11 in Joel's bedroom. Scott Cutler (who had
graduated from the group a couple of years before) used his TRS-80
Model II to create a ZIP for a TRS-80 Model I. As 1980 dawned,
Infocom spent a large portion of its bank account to purchase a Model
I, and Scott and Marc demonstrated that Zork I was alive in it by
starting the game and actually collecting points with the incantation
"N.E.OPEN.IN." (It's certainly no less inspiring than "Come here, Mr.
Watson; I want you!")
Mike Dornbrook was enlisted to test Zork I for bugs and other bad
features, because he had some experience with computers but no
experience with the original Zork, exactly like our intended audience.
(One of his contributions was the alternate -- and, some say, more
logical -- solution to the Loud Room puzzle, which was added only
after the first users of Zork I asked so often for hints for that
puzzle.) He played it so much that he memorized the entire geography,
and he fell in love with the game. He was convinced that it would
attract a cult following, although others thought it would last maybe
a year on the market and then fade away, like a video game. He urged
the company to start planning spin-off products, like maps, hints,
posters, T-shirts, etc. So the first published release of Zork I had
another feature added, a "small piece of paper" in the artist's studio
that said something like "Write to Infocom, P.O. Box 120, Cambridge,
Mass. 02142 for info on other products, including Movement Assistance
Planners (M.A.P.s) and Hierarchical Information for Novice Treasure
Seekers (H.I.N.T.S.)." Besides leaving the door open for an
after-market in Zork accessories, we wanted to start building a mailing
list of customers for future direct mailings (like the one you are
reading!).
Now that the company had a flesh-and-blood product, how could a small
group of hackers market and sell it? One possibility was to produce it
ourselves and distribute it through computer chain stores. But that
meant devoting time and energy to finding suppliers, producing
packages, supporting users, and so on. Another possibility was to
contract with a software publisher, but which one? Joel contacted
Microsoft, but they were already publishing the original "Colossal
Cave" adventure game -- the one that inspired Zork -- and by the time
Zork fan Bill Gates heard of our offer, Infocom was deep in
negotiations with Personal Software Inc. (PS).
PS had several good features: it was the first true publisher of
software developed by others; it was the leading publisher of computer
games at the time; and it had strong ties to Software Arts Inc., where
VisiCalc was invented (_requiescant_in_pace_), and where Zork I was
demonstrated in February 1980. PS agreed in June to publish Zork I
and sent us an advance on royalties, our first bonafide income! Sales
began in December, and over the next nine months PS sold about 1500
copies of the TRS-80 version. *
Also in June, we paid for a search of trademark records in preparation
for registering "Zork" as our own trademark. We discovered that
Mattel Inc. had registered "Mighty Zork" in 1973 for a toy model
motorcycle, but that registration was cancelled in October 1979.
Other trademarks discovered in the search were the likes of Zorr,
Zorak, Zark, and Zowees (all by Mattel); Zogg, Zon, Zak, Zok, Zot,
Zonk, and Zerak; and variations on Mork and Ork (by Paramount
Pictures). Not to mention the Zork Hardware Company of El Paso and
Albuquerque.
We had another product in which PS had no interest: the PDP-11 version
of Zork I. We sent product announcements to various places, including
a newsletter for PDP-11 users, and as a result, the first copy of Zork
I sold was a PDP-11 version! It came on an eight-inch floppy disk
with a manual that I wrote and Joel had reproduced from a typewritten
master.
By the end of 1980, the version of ZIP for the Apple II had been
created by Bruce, who had designed puzzles for the original Zork
before graduating from M.I.T. and going to work for Apple Computer
Inc. Apple Zork I proved more popular than the TRS-80 version; PS
sold over 6000 copies in eight months.
The first press reviews of Zork I were encouraging. In February 1981,
BYTE magazine said, "No single advance in the science of Adventure has
been as bold and exciting as the introduction of Personal Software
lnc.'s _Zork,_The_Great_Underground_Empire._ . . . That the program is
entertaining, eloquent, witty, and precisely written is almost beside
the point. Unlike the kingdoms of the Adventures for machines with 16K
bytes of memory and far from the classic counter-earthiness of the
Colossal Cave in the original Adventure, Zork can be felt and touched
-- experienced, if you will -- through the care and attention to
detail the authors have rendered. . . . [A] most excellent and
memorable work of computerized fiction."
Mike Dornbrook was enlisted again to fulfill mail orders for
personalized hints. Joel collected orders from the post office box,
passed orders for maps and posters to his Significant Other for
fulfillment, gave requests for hints to Mike, and gave me the numerous
small checks to deposit in the bank. Mike created personalized hints
off the top of his head, typing them on an old office typewriter.
(When Mike started business school in September 1981, he founded a
separate company, the Zork User's Group, and took over all mail-order
sales. Only then did he computerize the operation. In 1983, Mike
came back to work for Infocom, bringing Z.U.G. with him.)
Meanwhile, Dave was designing Zork II. At first, the most
straightforward approach seemed to be to use everything left out of
Zork I and simply convert it from MDL to ZIL. But Dave's active
imagination kept inventing new puzzles that virtually begged to be
implemented. So the final design left out the Royal Puzzle and the
"end-game" (both to appear in Zork III) and instead included the
Wizard of Frobozz, the garden, and the new diamond maze. (The last
was re-oriented to the compass based on Mike's belief that "southpaw"
should be a hint.) The last of the original puzzles -- the long slide
and "sending for the brochure" -- were left out of Zork III and didn't
reappear until Sorcerer.
Zork II was offered to PS in April and licensed in June 1981, about
the same time that Joel graduated and became Infocom's first salaried
employee. But we had serious concerns about PS's commitment, even to
Zork I. After an initial rush of advertising, Zork I seemed to join
PS's range of products as just another game. We were eager to make
new versions and new titles -- including Zork III, "Zork: the Mystery"
(Deadline), and "Zorks in Space" (Starcross) -- but not if our
publisher wasn't also eager. The fact was that PS was planning to
drop its line of entertainment software -- since their titles neither
sold well over the long term nor brought in enough money to satisfy
them -- and to change its name to Visicorp in order to identify
closely with its "Visi-" series of business products. **
It now appeared that we had two choices: to negotiate and contract
with another publisher (and to hope for more satisfaction), or to take
the plunge and _become_ a publisher. We definitely preferred the
second choice, but that required office space, production facilities,
an advertising agency, and so on -- and most of all, money. But we
threw caution to the wind, and hired Mort Rosenthal (who later founded
Corporate Software Inc.) as marketing manager, who found a time-shared
office in Boston's venerable Faneuil Hall Marketplace, a time-shared
production plant in Randolph, an ad agency in Watertown, an
order-taking service in New Jersey, a supplier of disks in California,
and so on. The money came both from the company's founders and from a
bank loan that they personally guaranteed.
We announced Zork II and our new role as publisher with a Christmas
promotion as eye-catching as we could afford. Thanks to our ad
agency, we had a new style of packaging for both Zorks (the
stone-built letters that are still in use), a counter display for
stores, ads in major computer magazines, and direct-mail ads for
dealers. We also bought PS's entire inventory of Zork I (except the
TRS-80 version, which they still wanted to sell) to prevent them from
"dumping" it on the market at bargain prices and lowering the public's
image of "Zork" in general. Our first shipment went out just in time
for Christmas sales.
On New Year's Day 1982, we moved the company to larger space at the
far end of Cambridge -- 55 Wheeler Street. Now we had office space
for everyone, especially for Marc (now vice-president for product
development) to finish Zork III. And we had enough space to set up
all the personal computers -- instead of shuffling them from one
person's home to another -- for testers to use, and for programmers to
create or adapt ZIPs for Atari, CP/M, IBM PC, and other machines.
Zork III was finished in the autumn, about the same time that the
company began hiring people to begin developing its first business
product. But that's another story.
* Zork I came under the wing of PS's New Products Manager, a fellow
named Mitch Kapor, who later founded Lotus Development Corp.
** In December 1984, after a long legal tangle with Software Arts over
VisiCalc, Visicorp eventually merged into one of its own spin-off
companies and disappeared.
[end]
Gary L Snethen
>The human eye picks up only three colors, in different receptors (cones?):
>red, green, and blue. All shading is done by the ratio of the receptors
>with each other. There is a slightly larger amount of one of these types
>of receptors than the other two. (I can't recall which one, but I think it
>was green.)
Yes, I believe it was green, and then red, and then blue. This leads to humans
perceiving green and yellow over the others... Some have theorized this was
an evolutionary development due to our sun's color.
>When a computer creates a color image (usually) it does so by assigning a
>certain number of bits to each of the primary colors. (again, red, green,
>and blue.) VGA comes in 4 and 8 bit flavors, (2^4 == 16, 2^8 == 256) , so
>the number of colors seen in VGA is either 16 or 256. Actually, VGA uses 8
>bits, but I believe that they swap between two sets of four bits each, or
>something, due to limitations on the memory throughput. (Add more memory to
>a 16 color VGA card will usually give you a 256 color VGA card.)
>Some of the nicer "super" VGA cards use 16 bits for color, giving 65536
>colors. Since 2^16 cannot evenly be distributed among the three primary
>colors, the extra bit is usually given to the primary that we can see more
>shades of. (2^6 greens, 2^5 reds, 2^5 blues).
>Most graphics workstations now come with 24 bit color. This gives 8 bits
>of color for each of the primaries, or about 16 million colors. Some of
>the more powerful graphics workstations now, and the graphics mainframes
>and such come with 48 bit color, giving two bytes of color information to
>each of the three primaries (giving 281 trillion colors).
>We've already passed the point of diminishing returns, however. The most
>significant difference is between 16 and 256 colors for most computer
>applications. For image-processing, 16 bit color is usually enough, with
>24 bit color used for serious tv-like color.
As I've already said, 24 bits in the system you've outlined isn't enough.
This only provides 256 shades of grey, which is insufficient... If the
2^24 colors were used optimally (according to the color reception curve of
our eyes), then they would be more than enough, I think... But they aren't
used this way.
>As for how many colors a person can see, its not a constant even for a
>single person in a single one-hour period. If the colors being viewed are
>very similar, say shades of green, the eye can pick up more colors within
>those shades. This is because the cones in the eyes that pick up that
>color get "tired", and the cones of the other colors have an easier time on
>picking out the information that they can read.
Very true...
>No matter how many colors a flat computer display can have, however, it
>will never be realistic enough to seem three-d. (I'm not counting stuff you
>can do with polarized glasses or other pheriferals.) This is because, for
>an object to seem three-d, it has to direct the light at a lot of different
>angles, which is not possible on a flat screen.
Aye? 3d requires no more color information that realistic 2d images.
3d perception comes primarily from three factors:
1) Shading
2) Bi-ocular convergence
3) Focusing depths
Of these three, number 2 is used the most. Your two eyes converge on the
various points you are looking at and the offset of other points (both behind
and in front of the observation point) are interpreted as depth by your brain.
This is the way the polarized glasses fool your eyes... They provide two
different images, one tailored for each eye with the offsets built into
the images.
Focusing information is evident in some people far more than others. Try
playing frisbee with one eye shut. If you play comfortably, then you probably
have good focal depth perception.
The fact that you can tell the shape of an object in a photograph is due to
the shading and perspective in the pictures. The shade of reflected light
is dependent on the angle that the normal of the surface makes with the light
source and with your eye.
If the shading of 24 bit graphics is good enough for 'photograph' quality,
then it is easily enough for 3d perception of depth, but this type of depth
perception does not (and can not) make you feel as though you can reach out
and touch the objects you see. Bi-ocular perception is the best at doing
that.
And on a related note, it's quite possible for a perfectly flat screen to
give you true bi-ocular representations without polarized glasses or any
headgear. Anyone who has ever seen a hologram (preferably a good one) knows
that flat plates can produce very realistic depth perception.
>This article turned out a lot longer than I initially expected. I guess
>the moral is that you probably don't need a 24 bit video card, and to
>invest in holographic displays.
>//Karthik
Mine too... ;)
---Xeno
Gary L Snethen
I'll challenge that any day...
There HAS to be qualification on statements such as these...
such as 'only distinguish 111 shades of grey in a single image' or whatever.
If you give me only two shades of grey at a time, I assure you that I can
perceive the difference between any two of a set of up to 200 shades if they
meet at a continuous border.
---Xeno
Gary L Snethen
>some combinations are more efficient than others. RBG is a good choice;
>although it obviously cannot match any possible spectrum, it can simulate
>the effects very well for the human visual system, since the eye can only
>sample three frequencies (two in cats, four in bees, it varies among
>species). Of course, beings with different visual systems will not see
>video screens, paintings, etc., in a different way.
Didn't you mean to write: '...beings with different visual systems *will* see
video screens, paintings, etc., in a different way?'
It should be readily apparent that since bees can perceive light in the
ultraviolet spectrum (and ants in the infrared I believe) that these
creatures will find televisions far far less realistic. Along the same lines,
nothing is special about red, green, and blue other than the fact that our
eyes react to these colors as 'primaries.' If I picked orange and violet as
my primary colors (no, there is no need for three of them, except that we have
three different types of color sensitive cells), then I would not be able
to make out a realistic image of most scenes produced with only these colors.
Also, there aren't seven colors in the rainbow --- at least not universally.
We perceive seven very different colors because of the design of our eyes.
If we ever meet an alien race, they most likely will not think that our
televisions are all that great.
Wouldn't it be interesting if our eyes worked like our ears? Individually
picking out thousands of different frequencies? A television screen image
of an ocean sunset would look incredibly dull to you. For an analogy, it would
be like listening to a chord of three different tones changing their relative
intensities as opposed to hearing the waves crash on the rocks, seagulls
chatting in the background, children playing in the water, and the wind
blowing past your ears.
And as should be apparent, you wouldn't be able to understand the 'image'
even though your eyes would be superior. No more than you could recognize
the the tone chord droning on and on if I played it for you now.
>We covered the number of possible colors only briefly, and I don't remember
>it. One interesting point is that the eye can differentiate far more
>colors than it can recognize; i.e., two shades might look the same when
>viewed separately, but might be easily distinguishable when together.
>DHT
>ObIntFict: I had real problems playing Deadline because the rooms were so
>undetailed. A room would have a bed, a table, and a chair, each totally
>without components. I realize that this means that searching rooms in
>detail is not productive, but it ruined the image for me.
I agree... I really didn't like Deadline too much. It seemed to me that you
had to get lucky and be in the right place at the right times.
---Xeno
Huisjes MJ
[ Stuff about foundation of Infocom deleted ]
....
} product. But that's another story.
} * Zork I came under the wing of PS's New Products Manager, a fellow
} named Mitch Kapor, who later founded Lotus Development Corp.
} ** In December 1984, after a long legal tangle with Software Arts over
} VisiCalc, Visicorp eventually merged into one of its own spin-off
} companies and disappeared.
} [end]
Please, please, continue. Interesting stuff. How did it continue with
Infocom and how did it end.
--
Maarten Huisjes. m...@cs.vu.nl (192.31.231.42)
(..!uunet.uu.net!cs.vu.nl!mjh)
Nathan Torkington
rec.games.int-fiction - please watch your newsgroups lines.
Thanks,
Nat
(deputy net.pit-bull :-)
Joseph M. Newcomer
colors (Was Re: .. by Karthik P Sheka@cunixb.c
> single person in a single one-hour period.
Many years ago, around the age of 11 or so, I wondered why I saw
slightly different colors from my left and right eyes. One eye seems to
give a slightly yellow cast to what I see, and the other a slight blue.
I can't tell offhand, because it has been years since I played with
this, and it only happens when I'm looking at something brightly lit,
like sunlight on a white bedsheet (I discovered this when trying to
avoid getting up early...)
However, in later years I discovered that I have a red/green color blindness
(which surprised me, as I can readily tell red from green, but I can't find
the numbers and shapes on the standard charts for colorblindness testing)
It is apparently severe enough to disqualify me from military service.
So tell me: what does red look like to you?
joe
Allen Smith
> In article <1992Oct13.2...@news2.cis.umn.edu> thor...@mega.cs.umn.edu (David H. Thornley) writes:
>
> A good article, but I have a bit more information:
>
> > RBG is a good choice;
> > although it obviously cannot match any possible spectrum, it can simulate
> > the effects very well for the human visual system, since the eye can only
> > sample three frequencies (two in cats, four in bees, it varies among
> > species).
> This is one point. It appears that some human eyes can view four frequencies.
> There appear to be two variants of the green detecting cones (with only a
> slight variation in the frequeny). Some people have only one variant, but
> some (mostly women) have both.
Interesting. Any references, info on what this effectively does,
basis of it (genetic, etc.)?
>
> Another thing is that color-blindness does not only disable one to
> distinguish two colors, but might also enable one to distinguish two
> other colors! A well known (amongst some people) example is in a fairly
> standard color-blindness test. The victim is shown figures consisting of
> different colored circles. The victin should tell what digit he is seeing,
> if any. For one of the examples a non-color-blind person will not see
> anything, but a red-green color-blind person will see a digit.
This effectively comes about because the red-green color-blind
person will distinguish on the basis of shading what would otherwise be
obscured by the colors.
-Allen
Deb Schwartz
>
>money can buy for the PC." On the Internet, there are over a million
>intelligent "peripherals".
>
used to work on. It used a hierarchical model database, and the way it
was supposed to work was that the uppermost level parent was the main
machine (say a mainframe or Unix file server) and all the children were
supposed to be its peripherals. Well, the company used a lot of IBM PCs as
dumb terminals networked to their IBM mainframes. Guess what. There were
a bazillion IBM PCs in the database designated as main machines that had IBM
mainframes as peripherals.
Yurk.
------
Debbie Schwartz // d...@voodoo.boeing.com // or uunet!bcstec!voodoo!das
[usual disclaimers apply]
Kenneth Sloan
>In article <75...@charon.cwi.nl>, d...@cwi.nl (Dik T. Winter) writes:
>> In article <1992Oct13.2...@news2.cis.umn.edu> thor...@mega.cs.umn.edu (David H. Thornley) writes:
>>
>> A good article, but I have a bit more information:
>>
>> > RBG is a good choice;
>> > although it obviously cannot match any possible spectrum, it can simulate
>> > the effects very well for the human visual system, since the eye can only
>> > sample three frequencies (two in cats, four in bees, it varies among
>> > species).
>> This is one point. It appears that some human eyes can view four frequencies.
Human photoreceptors do not respond to single frequencies. Each
population (rods and R,G,B cones - or L,M,S cones if you prefer)
responds to a wide spectrum - the differences in the types are primarily
in the location of the spectral sensitivity curves.
Blue cones (Short wavelength sensitive) are one distinct class. They
differ from other cones in morphology, distribution, and connectivity.
Green and Red cones (Medium and Long wavelength sensitive) form another
class. The two sub-classes have essentially the same shape curves, but
differ in the location of peak sensitivity. I don't believe that any
other differences (for example, in distribution or connectivity) have
been demonstrated, yet.
Recent color matching evidence suggests that there are at least two
distinct Green (Medium) populations, and (less evidence here) at least
two distinct Red (Long) populations. All of these studies have been
done only on males. It is entirely possible that all of these cone
types and subtypes may be found in a single individual.
[Quiz question: if you were studying these phenomena, why would you
study males first? What factors might cloud your evidence if you
included females? How and why are males simpler than females?]
All of this diversity hardly matches the turtles, some of which have as
many as 7 different cone types.
--
Kenneth Sloan Computer and Information Sciences
sl...@cis.uab.edu University of Alabama at Birmingham
(205) 934-2213 115A Campbell Hall, UAB Station
(205) 934-5473 FAX Birmingham, AL 35294-1170
Eric S. Raymond
> [Quiz question: if you were studying these phenomena, why would you
> study males first? What factors might cloud your evidence if you
> included females? How and why are males simpler than females?]
As a recent series of beer commercials might put it, "Y ask Y?".
--
Eric S. Raymond <e...@snark.thyrsus.com>
joev dubach
was more than one.
Joev
--
_____________________________________________________
DDDDDDDDD JJJJJJ | Joev Dubach
D J J | dub...@husc.harvard.edu
D J J | 249 North Mail Center
D D J J | Harvard University
DDDDD * JJJJJJ * | Cambridge, MA 02138
ajb...@ritvax.isc.rit.edu
>What were the two solutions to the Loud Room? I hadn't known there
>was more than one.
>
>Joev
>--
Technically, there's only one "true" solution to the Loud Room; the other
is something of a joke that goes back to the days of the original Adventure I
believe.
(**** spoilers follow ****)
The "true" solution is to temporarily cut off the flow of water through
the dam, and while the water level is rising, to run down to the quiet
Loud Room, grab the bar, and get out before the water goes over the dam
and things get noisy again.
The other is to type "echo."
Alex
Chris Flatters
>What were the two solutions to the Loud Room? I hadn't known there
>was more than one.
One involves the properties of the room.
The other involves getting rid of the loud noise.
Chris Flatters
cfla...@nrao.edu
Russell L. Bryan
dub...@husc10.harvard.edu writes:
>What were the two solutions to the Loud Room? I hadn't known there
>was more than one.
Man, how quickly do some of your servers kill messages on this group?
<SPOLER>
I'll make this quick --
Solution #1 -- say "echo" in the room.
Solution #2 -- Shut down the dam, go to the echo room -- echo is gone
until the dam refills.
Stu Galley
>
>Please, please, continue. Interesting stuff. How did it continue with
>Infocom and how did it end.
>--
>Maarten Huisjes. m...@cs.vu.nl (192.31.231.42)
> (..!uunet.uu.net!cs.vu.nl!mjh)
That's all the written history that I know of, except for this bit
from another news group. -- Stu Galley <Gal...@Think.com>
----------------------
Subject: ADMIN: comp.sys.ibm.pc.games - Frequently Asked Questions - Read before posting
15: Where can I get Infocom games? Can somebody mail me a copy (since they're
out of business anyway (Is that legal?) What happened to them anyway?
A: [Thanks to Dave Lebling (Infocom co-founder) for the definitive
info on this]
...
Infocom never went out of business. It went deeply into debt to
develop a database product (named Cornerstone) that was a commercial
flop. It went shopping for a merger and found Activision, which
later changed its name to Mediagenic. What did happen is that
in May of 1989 Mediagenic closed down the "real" Infocom in
Cambridge, MA, and laid (almost) everyone off. All the releases
up through Zork Zero, Shogun, Journey, and Arthur were developed
in Cambridge.
Mediagenic licensed the UK rights to the games to Virgin Mastertronic
about two years ago.
Mediagenic went nearly bankrupt, was taken over by outside investors,
and taken through a so-called "pre-packaged Chapter 11 bankruptcy" in
January, 1992. As part of that process, they changed their name back
to Activision, moved from Silicon Valley down to LA, and recently
merged with a company owned by the investors (called The Disc
Company).
[end]
Paul Ashley
>In article <Bw8pt...@cs.vu.nl> m...@cs.vu.nl (Huisjes MJ) writes:
>>
>>Please, please, continue. Interesting stuff. How did it continue with
>>Infocom and how did it end.
I quote from GAMES Magazine, Dec. 92, page 63, in the GAMES 100 list:
THE LOST TREASURES OF INFOCOM
Activision; Vol. I $70, Vol II $50, CD-ROM $80; IBM, Mac, Amiga (Vol I only)
What a bargain! Infocom, the most creative force in all-text interactive
fiction games, melded with Mediagenic several years ago and for a while
seemed to have disappeared. Activision, Mediagenic's new identity, has
now reissued the 33 greatest Infocom games in two volumes (20 in Volume I,
13 in Volume II): the Zork series, Starcross, Suspended, The Hitchhiker's
Guide to the Galaxy, Planetfall, Trinity, A Mind Forever Voyaging, et al. - -
with reproductions of the original maps, booklets, and the other stuff
that made Infocom games so special. Not to be missed.
What more needs to be said?
-Paul "Monty" Ashley
(Y'know, I once cowrote a book on Infocom games. The publisher (Datamost)
went bankrupt a week after the book went out. <mutter mutter>)
(Infocom Marathon of the Minds for Bureaucracy. Member of the winning team)
Lennart Regebro
>THE LOST TREASURES OF INFOCOM
>Activision; Vol. I $70, Vol II $50, CD-ROM $80; IBM, Mac, Amiga (Vol I only)
>
>What a bargain!
>the Zork series, Starcross, Suspended, The Hitchhiker's
>Guide to the Galaxy, Planetfall, Trinity, A Mind Forever Voyaging, et al. - -
>with reproductions of the original maps, booklets, and the other stuff
>that made Infocom games so special. Not to be missed.
>
>What more needs to be said?
Hum. What about where you can get it from. I prettyr sure this won't end up in
my local swedish computer shop. But you'll never know. They're pretty amazing
somtimes...
Lamar Owen
[rec.games.int-fiction removed from newsgroup lines]
> In article <0eZmsB...@lorc.UUCP> lo...@lorc.UUCP (Lamar Owen) writes:
> > [ . . . . . . ] . Oh, but you meant a *single* compute
> >not a network... Hmmm... Well, the Apollo Domain system blurs that distincti
> >being that memory is shareable amongst machines, processes are shareable,
> >video is shareable (ever seen net_bounce on an Apollo? Bounces an object acr
> >multiple workstation's screens), the mouse is shareable (move your mouse cur
> >to another workstation and open a window there).
>
> Thank you for your kind words for our systems. Unfortunately, you are incorr
> Memory, processes, etc. are no more sharable than they are on any network of
> workstations connected to a LAN.
Let me rephrase: virtual memory is shareable, if the paging device is not on
the local drive. The point I was making (which I *just might* have gotten
a little carried away in my enthusiasm for what Domain/OS will *allow*) is
that LANs in general (and Apollo in specific, since I have a small (2 machine)
network at home) is that the distinction between the processors is blurred,
not taken away completely. Technically speaking, with IPC over a LAN, you have
a loosely coupled multiprocessor.
> What the Apollo Domain network offered was a real network-wide file system th
> was always there (you didn't need to explicitly mount remote disks), and had
> necessary primitives to make read/write remote file access usable without the
> problems that multiple independent write attempts cause on some other systems
This was Domain's best feature (I assume you have the list of features that
was posted to comp.sys.apollo a month or two back; if not, I can e-mail you
a copy from my archive). The entire network was there for you without
explicit mounts. Everything was already mounted (if you ran ns_helper;
otherwise you had to run ctnode on each system that needed to access the node's
disk--at least it was a one-shot thing) on the network root (// for non-Apollo
people). No cross-mounts were necessary.
> The net_bounce demo program makes clever use of the Network Computing Service
> facilities to coordinate the display of an object between several cooperating
> processes. The mouse moving between screens was only possible on a project
> that I don't believe ever made it to the product line - multiple display head
> on a single workstation.
I have seen a demo that did mouse cursor movement between workstations. It was
just that, though--a demo. I wish I could find a copy of net_bounce.... IPC
at its finest.
> A modern workstation with the Andrew File System, Posix threads, and the OSF
> Distributed Computing Environment can do most things that the Apollo systems
> could do. The major distinction is that Apollo has had this stuff for years!
Yep, this "modern" workstation can do *most* of what Domain could do five years
ago. Ain't progress wonderful!??!
I love my Apollo...(not as much as my fiance, but that's a different story...)
With spm running on both machines, the global user registry, and the network
file system, I can log in on either workstation and do anything, anywhere,
without hassle. It's a sweet system.
I see you are in Apollo. What relationship do you have with the older boxes
(DN3x00, for instance)? My home net is two DN3500's with 32MB RAM each, one
has a single 150MB drive and the other has four (two controllers, two disks
per controller) 150's sector striped into a single 600MB volume. This machine
has a cartridge, is home for the AA, and runs glbd, llbd, spm, and rgyd. The
other machine has a PC-ElevATor 386 and a floppy. Both have 8-plane 1024x800
graphics systems, driving 19 inch color monitors. This beast runs SPICE very
well!
> John Francis jo...@apollo.hp.com
Matt Ackeret
pas...@crash.cts.com writes:
>THE LOST TREASURES OF INFOCOM
>Activision; Vol. I $70, Vol II $50, CD-ROM $80; IBM, Mac, Amiga (Vol I
only)
The Lost Treasures of Infocom will be available for the GS in a week or so
from the Big Red Computer Club. They distribute a lot of other companies'
Apple II and IIGS products too (that is, companies that aren't actively
selling the products themselves, and new programs from other companies)
very inexpensively.
Anyone who is interested, look in a copy of InCider for the address, or
e-mail me and I'll send it to you. (I don't have it with me now).
Darin Johnson
>>Activision; Vol. I $70, Vol II $50, CD-ROM $80; IBM, Mac, Amiga (Vol I
>only)
I just picked this up for Amiga, $49! That's $2.50 per game...
Now if I can stick to my promise not to buy any more programs
until I finish them all..
--
Darin Johnson
djoh...@ucsd.edu
This is the first time I've ever eaten a patient -- Northern Exposure